Given the task definition, example input & output, solve the new input case.
You are given a short paragraph, a question and two choices to answer from. Choose the correct answer based on the paragraph and write the answer(not the key).
Example: Paragraph: Many of the worlds people live with water scarcity, and that percentage will increase as populations increase and climate changes.
 Question: John's town used to have lots of water, back when there were only a few hundred people. However, now that the town holds several thousand people, the water availability is 
 Choices: A)scarce 
B)plentiful
Output: scarce
Based on the information given in the paragraph, population growth will make water more scarce, so that is the correct answer.

New input case for you: Paragraph: The upper rock layers are much younger.
 Question: Rich was examining a cliff face. Which part of the cliff is younger, geologically speaking? 
 Choices: A)the base 
B)the top
Output:
the top