Answer:
First option
Step-by-step explanation:
Muscular strength is basically using your muscles to apply force to an object or to carry out an act. In this case, push-ups up require you to use the muscles in your arms to push yourself off the ground. The more muscular strength you have the more push-ups you can complete at one time. Which means push-ups require muscular strength in order to complete, therefore the first option or "push-ups" is your answer.
Hope this helps.