Which is an example of satire?

a. the family members in a short story have an elephant living in their dining room that they refuse to discuss, just as they refuse to deal with other problems.

b. a play about a deaf character includes jokes that are funnier in sign language, so audience members who don't know sign language are left out.

c. a film's teenage character rolls her eyes and says, "sure, i'd love to," when her mother asks her to clean the toilet.

d. in a novel, the partners in a couple have good news they hide from each other, unaware that the other is doing the same thing.

i believe c is sarcasm not satire but i don't understand the difference between the other 3 answers. if you could explain the answer to me that would be great.