Read the excerpt about exercise. Many people include exercise in their daily lives, which is a great idea. Many exercisers choose aerobic activity, such as running, cycling, or swimming to make their body burn energy. These types of exercises raise the heart rate and increase breathing to get oxygen to the muscles. Aerobic exercise is absolutely necessary to keep the heart and lungs healthy, and it does burn calories. Which best explains why the author uses definition to guide readers through this part of the text? to help the reader better understand what aerobic exercise is to suggest that aerobic exercise is better than other types of exercise to point out the advantages and disadvantages of aerobic exercise to recommend that people try several different types of aerobic exercise