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).
Q: Paragraph: Smaller tributary glaciers, like tributary streams, flow into the main glacier in their own shallower U-shaped valleys.
 Question: What would happen to the size of the valley created by a tributary stream if the size of the stream were to be increased? 
 Choices: A)the valley would be shallower 
B)the valley would be deeper
A:
the valley would be deeper