Answer:
The correct answer is D. rock climbing and hiking
Step-by-step explanation:
Hiking and rock is the pair of activities which most vigorous physical activity outside the school. Hiking and rock climbing requires lots of stamina and strength for a long time.
In rock climbing a person climb against gravity, therefore, it requires lots of energy, strength, and stamina. It is one of the vigorous physical activity and in one hour 500 to 900 calories can be burned.
Hiking is another vigorous physical activity that includes long walks. It comes under aerobic physical activity which boosts bone density. Therefore the correct answer is D.