The correct answer is D. Both A and C (Heredity and Environment)
Step-by-step explanation:
Fitness potential can be defined as the fitness level you can achieve through training, time, effort, etc. or your latent qualities and abilities to be physically fit. This potential is defined by heredity because genes can influence your endurance, body composition, size and shape of your body, etc. that are related to physical conditions.
Additionally, the environment plays an important role in your fitness potential because factors such as nutrition, habits, age, etc. that are external also influence your fitness level because they can help you to reach a higher or lower level as they limit you physically. According to this, both heredity and environment (A and C) are aspects that can set physical limits to our fitness potential.