What are some of the possible short and long term medical concerns for crew members on longer space exploration trips?

Several things can happen to humans who engage in space exploration, many of them relating to how gravity changes and the new environment they have to live in. Changes in gravity can cause bones to lose minerals, exposition to radiation can increase the risk of getting cancer, the diet is not the most nutritious, and without exercise, the body can deteriorate easily. There is also the chance that they might lack vitamins necessary for people, such as vitamin D that comes from the sun and that we usually get by going outside.

Explanation:

"a" because he is appealing to logic as oppose to appealing to the audience's emotions.