The main character is trapped, but he can get out with a key.
There's nothing that indicates imminent danger or any external tension, so we can discard the idea of fighting for survival or even being a prisoner in a wartime (that would be a stretch). Being locked up might be a representation of many things, but being exiled is most likely not one of them. Exile envolves distance and loneliness, not being locked up.
In the end, the idea of being alone, trapped in barrel cage with a lock fits the idea of "figuring a way to escape" (there's a lock, it means that there's a key).
The correct answer is:
A. The main character is trapped by a life choice and must figure out a way to escape.