From what I read, I would say B.
An oxymoron is a figure of speech that combines two seemingly contradictory or opposite ideas to create a certain rhetorical or poetic effect and reveal a deeper truth. Generally, the ideas will come as two separate words placed side by side. The most common type of oxymoron is an adjective followed by a noun.
After several hours of deliberation the jury returned with the verdict—not guilty.
A best supports the argument because it is the only answer that describes the pros of having mice as pets, while the others provide tips and facts upon adopting them.
