You will be given a definition of a task first, then some input of the task.
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).

Paragraph: Smaller tributary glaciers, like tributary streams, flow into the main glacier in their own shallower U-shaped valleys.
 Question: Sandra sees a huge glacier, and notes that it has smaller tributary glaciers flowing into it, in valleys that are 
 Choices: A)shallow 
B)deep
Output:
shallow