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.

[EX Q]: Background Paragraph: Baker's yeast is the common name for the strains of yeast commonly used in baking bread and bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. Baker's yeast is of the species Saccharomyces cerevisiae,[1] and is the same species (but a different strain) as the kind commonly used in alcoholic fermentation, which is called brewer's yeast.[2] Baker's yeast is also a single-cell microorganism found on and around the human body. 
Story: the students used yeasts in two different experiments: they baked bread using baker's yeast, and made beer, using brewer's yeast. They learned a lot about sugars and chemistry. 
Question: Which yeast is better for bakery products?
[EX A]: baker's yeast.

[EX Q]: Background Paragraph: Enzymes increase the rate of chemical reactions by reducing the amount of activation energy needed for reactants to start reacting. One way this can happen is modeled in the Figure below . Enzymes aren’t changed or used up in the reactions they catalyze, so they can be used to speed up the same reaction over and over again. Each enzyme is highly specific for the particular reaction is catalyzes, so enzymes are very effective. A reaction that would take many years to occur without its enzyme might occur in a split second with the enzyme. Enzymes are also very efficient, so waste products rarely form. 
Story: A scientist is testing chemical reactions. At first he tries mixing two chemicals together at a temperature of 85 degrees Celsius and labels it Trial A. He records the time for the reaction to complete at 2 minutes. Knowing that this isn't the temperature users at home will be combining the chemicals at he tries the reaction again at a more modest 65 degrees Celsius and labels this trial B. Noting this temperature the reaction takes almost 4 times as long which is completely unacceptable, He then gets an idea to add and enzyme designed specifically for these two chemicals and then tries the reaction at the modest 65 degrees Celsius again calling this one trial C. 
Question: Given that this enzyme is designed specifically for use with the chemicals in this experiment, will the reaction for trial C be faster or slower than the reaction in trial B?
[EX A]: faster.

[EX Q]: Background Paragraph: Biodiversity is determined by many things, and one of them is abiotic stress. If an environment is highly stressful, biodiversity tends to be low. If abiotic stress does not have a strong presence in an area, the biodiversity will be much higher.This idea leads into the understanding of how abiotic stress and endangered species are related. It has been observed through a variety of environments that as the level of abiotic stress increases, the number of species decreases. This means that species are more likely to become population threatened, endangered, and even extinct, when and where abiotic stress is especially harsh. 
Story: Italy had two distinct regions. Northern region where the animals are exposed to a lot of abiotic stress, and the southern region, where the animals experience almost no abiotic stress. 
Question: Which region had fewer species with populations threatened?
[EX A]:
southern.