TASK DEFINITION: You are given a background paragraph that describes one or more causal or qualitative relationships such as a relationship in economics or a scientific law and a story that makes use of the concepts or the relationship described in the provided paragraph. You are also given a question about the story that requires an understanding of the relationship described in the background paragraph and the story. You need to come up with an answer to the given question; the answer will be a span from either the question or the story. In order to correctly answer the given question, you need to understand the relationship mentioned in the background paragraph and should be able to use it to understand that in the story. Your answer can not consist of any word that is not mentioned in any of these: the background paragraph, the story, or the question. You can directly copy and paste a span from the story or the question while answering the given question.
PROBLEM: Background Paragraph: Protozoa generally feed by engulfing and digesting other organisms. As consumers, they have various roles in food chains and webs. Some are predators. They prey upon other single-celled organisms, such as bacteria. In fact, protozoa predators keep many bacterial populations in check. Other protozoa are herbivores. They graze on algae. Still others are decomposers. They consume dead organic matter. There are also parasitic protozoa that live in or on living hosts. For example, the protozoan that causes malaria lives inside a human host. For their part, protozoa are important food sources for many larger organisms, including insects and worms. 
Story: An astronaut has just landed on a new martian planet and encounters two different protozoa. The first protozoa he finds, protozoa X, is eating algae that is floating on top of water. The second protozoa, protozoa Y, is found eating bacteria. Upon further study, it is found that these are the only foods these two specific protozoa eat. 
Question: Which protozoa is a herbivore?

SOLUTION: protozoa X.

PROBLEM: Background Paragraph: Candied fruit, also known as crystallized fruit or glacé fruit, has existed since the 14th century. Whole fruit, smaller pieces of fruit, or pieces of peel, are placed in heated sugar syrup, which absorbs the moisture from within the fruit and eventually preserves it. Depending on size and type of fruit, this process of preservation can take from several days to several months.[1] This process allows the fruit to retain its quality for a year.[2]

The continual process of drenching the fruit in syrup causes the fruit to become saturated with sugar, preventing the growth of spoilage microorganisms due to the unfavourable osmotic pressure this creates.[3]. 
Story: Mary and Ann got some fruit as a gift from a friend. Mary decided to candy the fruit, while Ann decided to eat them fresh, Mary received plums, peaches, apples and oranges. Ann got pears, quince, cherries and blackberries. 
Question: Which fruit retained their quality longer plums or quince?

SOLUTION: plums.

PROBLEM: Background Paragraph: The example of someone having a positive experience with a drug is easy to see how drug dependence and the law of effect works. The tolerance for a drug goes up as one continues to use it after having a positive experience with a certain amount the first time.[38] It will take more and more to get that same feeling. This is when the controlled substance in an experiment would have to be modified and the experiment would really begin. The law of work for psychologist B. F. Skinner almost half a century later on the principles of operant conditioning, "a learning process by which the effect, or consequence, of a response influences the future rate of production of that response.[39]. 
Story: The cocaine club met to discuss their experiences. They all said they always had a great experience using cocaine and used the same amount each time. They told how many times they used cocaine. Mary used it 2 times, Patricia used it 3 times, Linda used it 5 times, Barbara used it 10 times, Elizabeth used it 15 times, Jennifer used it 20 times, and Maria used it 30 times. 
Question: Who has a higher tolerance for cocaine: Jennifer or Barbara?

SOLUTION:
Jennifer.