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: You may hear males "ribbiting," producing a mating call used to attract females to the bodies of water best for mating and breeding. Frog calls can occur during the day or night. Each frog species has a different call that is used to attract mates and warn off rivals. When a female picks a male whose call she likes, the male grabs her and squeezes across her back and around her abdomen. This causes the female to release her eggs. The male then fertilizes the eggs and, in some species, also guards them.
Story: Sandra liked all creatures but loved to study frogs. Her sister Julie studied more about fish and butterflies. They both loved nature.
Question: Which sister learned more about different calls used by different species of frogs?

Output: Sandra.

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: Human beings invented agriculture about 10,000 years ago. This provided a bigger, more dependable food supply. It also allowed people to settle down in villages and cities for the first time. Birth rates went up because there was more food and settled life had other advantages. Death rates also rose because of crowded living conditions and diseases that spread from domestic animals. Because the higher birth rates were matched by higher death rates, the human population continued to grow very slowly.
Story: A team of archaeologists studied two human settlements, village Alpha from about 11000 years ago and village Beta, which existed 9000 years ago. Village Beta was bigger, because their inhabitants already knew about and practiced agriculture.
Question: Which village had a smaller food supply?
Output: Alpha.