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: For a given medium, sound waves travel more slowly at lower temperatures.
 Question: When it is very cold what happens to the speed of items? 
 Choices: A)speed up 
B)slow down
Output:
slow down