I believe it is c. I am not 100% sure but I think that is the answer
They are called compound sentences.When 2 sentences are connected.
In mark twains piece of literature, the invalids story, irony is repeatedly used
- they don't want to get sick from the smell, but they eventually get sick from the coldness
- dramatic irony; the responder knows that a bag of cheese was left on the box, but the two men in the train don't know this