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: The closer together the particles in a longitudinal wave are, the greater the amplitude.
 Question: Fred found a longitudinal wave. The particles are getting closer together. The amplitude is 
 Choices: A)increasing 
B)decreasing
increasing