Answer:
4) doing sit-ups and push-ups
Explanation:
Between the options to pick from, the one that requires more physical exigence and envolve a major number of muscles is doing <em>sit-ups and push-ups.</em>
This semi-intense physical activity has a determined difficulty that makes it a complete exercise for all the extremities, fomenting the muscles movement, circulatory system, and works as a cardiovascular session as well.
The pushups are great for the upper body muscles, involving the pectorals, shoulders, deltoids, between others, And sit-ups work for all the abdominal section, benefiting the muscles and the digestive organs as well.