Given the task definition and input, reply with output. 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: At higher elevations, there is less air to press on a given area.
 Question: When we get to the top of a mountain the air is 
 Choices: A)more dense 
B)less dense
less dense