The one that you've circled (A) is the correct answer.
Increased muscle mass: Muscle mass naturally decreases with age, but strength training can help reverse the trend.
Stronger bones: Strength training increases bone density and reduces the risk of fractures.
Joint flexibility: Strength training helps joints stay flexible and can reduce the symptoms of arthritis.
Which is the greatest physical benefit from jogging?
Jogging is a great exercise to keep healthy, and can be great, benefiting you both physically and even mentally.
But, the greatest physical benefit from jogging is cardiorespiratory endurance.
Hope this helps, regards.
It is because the “building” word that denotes infrastructures is a gerund. Gerunds are nouns that came from verbs + a suffix “ing". So in this case, “building” comes from the verb “built" (which implies that something is already done building something) + the “-ing”.