Probably B. Having been informed
what do you need help with :)
I think one of the main reasons Mark Twain used a young boy as the main character and narrator of such a controversial novel filled with adult themes to convey the innocent side of these adult themes. Telling this story in the eyes of a teenage boy, the morality of these situations appears more obvious. Another reason why Mark Twain used a teenage boy as the main character and narrator in the novel is because it allows Twain to imply a comparison between the powerlessness and the vulnerability of a child and the powerlessness and vulnerability of a black man in the pre-Civil War era. He also may be using a child protagonist to dramatize the conflicts between societal and received morality on one hand and a different kind of morality based on experience and intuition.
Two advantages were that yes, it might've been really fun to float around weightless and see how liquids form into a ball. Another could also be that you wouldn't have to push or pull heavy things without gravity.
Although, there are some disadvantages. One is that your bones can become very weak and thin overtime because of weightlessness, your bones and muscles wouldn't have to work so much, so they get weaker. Also, you may get sick, your stomach will hurt and you might get dizzy after a while. This is caused because there's no gravity; humans are only used to gravity which on earth.
Hope this helps!