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.

Input: Consider Input: Background Paragraph: All of these animal behaviors are important. They help the animals get food for energy, make sure their young survive, or ensure that they, themselves, survive. Behaviors that help animals or their young survive, increase the animals' fitness. Animals with higher fitness have a better chance of passing their genes on to the next generation. If genes control behaviors that increase fitness, the behaviors become more common in the species. This occurs through the process of evolution by natural selection.
Story: David is a biologist. He was in the African savanna to study different species. Especially, he was interested in two species, rhinos and impalas. He noticed that in response to constant human encroachment of wildlife habitats, impalas have acquired some behaviors that help them and their young. Rhinos also have acquired some behaviors in response to the same threat. But their behaviors mostly failed them in that aspect.
Question: In which species the behaviors in question would be more common, rhino or impala?

Output: impala.

Input: Consider Input: Background Paragraph: Figure B above shows an important relationship between the wavelength and frequency of a wave. The top wave clearly has a shorter wavelength than the second wave. However, if you picture yourself at a stationary point watching these waves pass by, more waves of the first kind would pass by in a given amount of time. Thus the frequency of the first waves is greater than that of the second waves. Wavelength and frequency are therefore inversely related. As the wavelength of a wave increases, its frequency decreases. The equation that relates the two is.
Story: Jenna is studying waves and their related characteristics. Today, is she analyzing two different waves, wave D and wave M. Wave D has a very long wavelength, and wave M has a short wavelength. In order to verify her findings though, she is going to stand still and have both waves pass over her for the same amount of time and record the number of waves of each type that passed her.
Question: Will less wave D or wave M waves pass Jenna?

Output: Wave D.

Input: Consider Input: Background Paragraph: Besides anthropogenic productivity of the land, the biodiversity of degraded land also declines, as previously mentioned.[12] With less biodiversity, this ecosystem is less adaptable to when disasters strike it[11][8] It has a smaller available food supply, in terms of plants, for animals, who then may die out or more likely may relocate. Proof of this decline is that presently 15-20% of Tibetan Plateau species are now considered endangered; and now because of this animal and plant absence, the soil quality of these degraded lands is very poor.[1] It does not hold the necessary nutrients, such as water, nitrogen, and carbon, essential to either supporting life or inviting life back to that land.[6] As a result of such carbon and nitrogen loss in the Tibetan Plateau, $8,033/ha and $13,315/ha were respectively lost in economic terms. Soils are further weakened by dust storms whose frequency increases because of degradation.[11][4] Erosion of soil becomes a bigger problem, since no longer are there as many plants to anchor in the soil. In the northern Chinese province alone, 400 million are affected every year with an associated 54 billion yuan of annual economic loss due to grassland degradation.
Story: The southern province was exposed to intensive grazing for many years , and now soil quality is poor and dust storms are present. The northern province has more fertile soil, more trees.
Question: Which province experiences more dust storms?
Output: southern.