Final answer:
Sprinting belongs at the top of the physical activity pyramid as it is an intense anaerobic exercise which is done less frequently compared to moderate, everyday activities.
Step-by-step explanation:
The activity that belongs at the top of the physical activity pyramid for promoting health and fitness is most likely sprinting. This is because sprinting is an anaerobic exercise, which is typically placed at the top of the pyramid, above aerobic and flexibility activities. The physical activity pyramid is a visual guide that organizes different types of physical activities by how frequently they should be performed, with less frequent activities such as sprinting at the top, and more common, moderate activities like walking or cycling at the base.