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: When the heart expels more blood with each stroke, the heart has to beat less often in order to maintain the same volume of blood flow.
 Question: If Milo calms down and his heart starts pumping less blood with each stroke, what happens to his heart rate? 
 Choices: A)increases 
B)decreases
increases