Which of the following best describes muscular strength?

Muscular strength is best described as the ability to produce maximum force. This definition emphasizes the capacity of the muscles to exert force against resistance, which is typically measured during activities such as weightlifting or resistance training. Muscular strength is a key component of overall fitness and is critical for various physical tasks, whether in sports or daily activities.

The other options relate more to different aspects of physical fitness. For instance, the ability to resist fatigue pertains more to muscular endurance, which involves sustained performance over time rather than the peak force output. Similarly, the ability to sustain activity points towards endurance and aerobic capacity, focusing on the ability to perform at a moderate intensity over an extended period rather than the maximal force output of muscles. Lastly, the ability to perform aerobic exercise relates to cardiovascular fitness rather than strength, as it involves prolonged physical activity and the efficiency of the cardiovascular and respiratory systems.