practicing space walking counseling activities for tension exercising to maintain strength monitoring circadian rhythms
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Scientists noted that muscles and bones would need physical stress to remain healthy during manned space flights. Which of these had to be planned for because of this need?
Possibilities:
- practicing space walking
- counseling activities for tension
- exercising to maintain strength
- monitoring circadian rhythms

exercising to maintain strength