Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

[EX Q]: Context: How quickly is the human population growing? If we look at worldwide human population growth from 10,000 BCE through today, our growth looks like exponential growth. It increased very slowly at first, but later grew faster and faster as the population increased in size ( Figure 1.1). And recently, the human population has increased at a faster pace than ever before. It has taken only 12 years for the worlds population to increase from six billion to seven billion. Considering that in the year 1804, there were just one billion people, and in 1927, there were just two billion people (thats 123 years to increase from 1 to 2 billion), the recent increase in the human population growth rate is characteristic of exponential growth. Does this mean there are unlimited resources? Worldwide human population growth from 10,000 BCE through today. On the other hand, if you look at human population growth in specific countries, you may see a different pattern. On the level of a country, the history of human population growth can be divided into five stages, as described in Table 1.1. Some countries have very high birth rates, in some countries the growth rate has stabilized, and in some countries the growth rate is in decline. Stage 1 2 3 4 5 Description Birth and death rates are high and population growth is stable. This occurred in early human history. Significant drop in death rate, resulting in exponential growth. This occurred in 18th- and 19th-century Eu- rope. Population size continues to grow. Birth rates equal death rates and populations become stable. Total population size may level off. The United Nations and the U.S. Census Bureau predict that by 2050, the Earth will be populated by 9.4 billion people. Other estimates predict 10 to 11 billion. There are two different beliefs about what type of growth the human population will undergo in the future: 1. Neo-Malthusians believe that human population growth cannot continue without destroying the environment, and maybe humans themselves. 2. Cornucopians believe that the Earth can give humans a limitless amount of resources. They also believe that technology can solve problems caused by limited resources, such as lack of food. The Cornucopians believe that a larger population is good for technology and innovation. The 5-stage model above predicts that when all countries are industrialized, the human population will eventually level out. But many scientists and other Neo-Malthusians believe that humans have already gone over the Earths carrying capacity. That means, we may have already reached the maximum population size that can be supported, without destroying our resources and habitat. If this is true, then human overpopulation will lead to a lack of food and other resources. Overpopulation may also lead to increased disease, and/or war. These problems may cause the population of humans to crash. If these issues are not controlled, could the human population go extinct? Which of the above theories makes sense to you? Why? 
 Question: which is the last stage of human population growth?
[EX A]: total population size may level off.

[EX Q]: Context: New Orleans narcotics detective Anthony Stowe (Jean-Claude Van Damme) is a heroin addict who is teetering on the edge of oblivion, and he couldn't care less.At the moment, Stowe is trying to bring down his former partner Gabriel Callahan (Stephen Rea), who has become a drug kingpin. Callahan is trying to, and slowly succeeding at, taking over the New Orleans underworld.Stowe botches a sting operation against Callahan, resulting in the death of fellow cop Maria Ronson (Rachel Grant), whose fiancee, fellow cop Van Huffel (Adam Leese), is furious at Stowe. Chief Mac Baylor (Gary Beadle) has a very blunt chat with Stowe about it. Stowe is approached by fellow cop Walter Curry (Trevor Cooper) to help his nephew beat a drug-dealing charge. Stowe instead turns him over to Baylor, who fires him. After barricading himself in the station bathroom, Walter confronts an unrepentant Stowe and condemns him for betraying his fellow officers.Later, Van Huffel berates Stowe for getting Maria killed. Stowe responds by attacking Van Huffel in front of several officers. Later, Stowe meets with his estranged wife Valerie (Selina Giles), who tells him that she's pregnant, but that he's not the father. Valerie, whose marriage with Stowe is on the rocks, has been seeing a man named Mark Rossini (Mark Dymond), the gym teacher at the school she is principle of. But he may not be the father either. Stowe brashly accuses Valerie of being impregnated by Callahan, and Valerie tells him she never wants to see him again.The only thing keeping Stowe from total collapse is his dogged pursuit of Callahan. But he drunkenly stumbles into an ambush masterminded by Callahan, and is shot in the head by Callahan's right-hand man Jimmy (Stephen Lord).Stowe undergoes emergency surgery, and ends up in a coma. Months later, he recovers to the point that he opens his eyes, and is transported to his and Valerie's house to recover properly.Seven months after getting shot, Stowe has recovered a lot, although he must learn to walk and speak again. He manages to survive an attempt on his life, by someone who appears to be a cop. He's recovered enough to try to get his job back, but that's the one thing that Chief Baylor doesn't want to give him. The coma has led to his decision to become a better man, and to right some wrongs. He reconciles with his wife, although awkwardly, and gives Walter a check for $40,000, part of his insurance money that compensated his time in a coma. Finally, he visits the grave of fellow police officer Serge (William Ash), who once saved Stowe's life but has been killed by an unknown attacker following another failed sting operation.Valerie packs up to move out of the house so she can live with Mark, but after realizing the change that Stowe has undergone, she later decides to leave Mark and come back home. Stowe is convinced by his friend Chad Mansen (Wes Robinson) not to let his wife go, and Stowe goes after her. They miss each other by a few minutes.Just after Valerie returns and meets Chad, some of Callahan's men show up. Jimmy kills Chad, and kidnaps Valerie. Stowe returns to the house, and finds Chad's body, along with Jimmy waiting for him.Van Damme promoting the film in 2007Jimmy takes Stowe to a warehouse where Callahan is waiting. Along the way, Stowe manages to overpower Jimmy and take his gun, but he finds that the odds against him are impossible- and Callahan has Valerie hostage. Van Huffel is revealed to be Callahan's mole on the police force, and the sting operation at the beginning of the film was a set-up. Walter suddenly arrives and saves Stowe. Together they kill all of Callahan's men, including Jimmy and Van Huffel, as Callahan tries to escape with Valerie to his helicopter. Just as Callahan is about to reach it, Stowe appears.In the European DVD ending, each fire a shot that kills the other. Valerie cries out 
 Question: Who saves Stowe?
[EX A]: serge

[EX Q]: Context: The process of DNA replication is not always 100% accurate. Sometimes the wrong base is inserted in the new strand of DNA. This wrong base could become permanent. A permanent change in the sequence of DNA is known as a mutation. Small changes in the DNA sequence are usually point mutations, which is a change in a single nucleotide. Once DNA has a mutation, that mutation will be copied each time the DNA replicates. After cell division, each resulting cell will carry the mutation. A mutation may have no effect. However, sometimes a mutation can cause a protein to be made incorrectly. A defect in the protein can affect how well the protein works, or whether it works at all. Usually the loss of a protein function is detrimental to the organism. In rare circumstances, though, the mutation can be beneficial. Mutations are a mechanism for how species evolve. For example, suppose a mutation in an animals DNA causes the loss of an enzyme that makes a dark pigment in the animals skin. If the population of animals has moved to a light colored environment, the animals with the mutant gene would have a lighter skin color and be better camouflaged. So in this case, the mutation is beneficial. If a single base is deleted (called a deletion, which is also a point mutation), there can be huge effects on the organism, because this may cause a frameshift mutation. Remember that the bases in the mRNA are read in groups of three by the tRNA. If the reading frame is off by even one base, the resulting sequence will consist of an entirely different set of codons. The reading of an mRNA is like reading three-letter words of a sentence. Imagine the sentence: The big dog ate the red cat. If you take out the second letter from "big," the frame will be shifted so now it will read: The bgd oga tet her edc at. One single deletion makes the whole sentence impossible to read. A point mutation that adds a base (known as an insertion) would also result in a frameshift. Mutations may also occur in chromosomes ( Figure 1.1). These mutations are going to be fairly large mutations, possible affecting many genes. Possible types of mutations in chromosomes include: 1. Deletion: When a segment of DNA is lost, so there is a missing segment in the chromosome. These usually result in many genes missing from the chromosome. 2. Duplication: When a segment of DNA is repeated, creating a longer chromosome. These usually result in multiple copies of genes in the chromosome. 3. Inversion: When a segment of DNA is flipped and then reattached to the same chromosome. 4. Insertion: When a segment of DNA from one chromosome is added to another, unrelated chromosome. 5. Translocation: When two segments from different chromosomes change positions. Many mutations are not caused by errors in replication. Mutations can happen spontaneously, and they can be caused by mutagens in the environment. Some chemicals, such as those found in tobacco smoke, can be mutagens. Sometimes mutagens can also cause cancer. Tobacco smoke, for example, is often linked to lung cancer. 
 Question: what type of mutation occurs when a segment of dna is flipped and then reattached to the same chromosome?
[EX A]:
inversion