The correct answer:
D. Brutus
Here's a bit more of the context of that quote from Act II, Scene 1:
O conspiracy,
Sham'st thou to show thy dang'rous brow by night,
When evils are most free? O, then, by day
Where wilt thou find a cavern dark enough
To mask thy monstrous visage? Seek none, conspiracy.
Hide it in smiles and affability;
For if thou path, thy native semblance on,
Not Erebus itself were dim enough
To hide thee from prevention.
Brutus was speaking about the conspiracy to assassinate Julius Caesar. Even if the participants in a conspiracy think they are pursuing a good cause, the evils of conspiracy are evident from the fact that it must be masked and hidden behind smiles and pleasantries.
William Shakespeare's play, Julius Caesar, is believed to date from 1599. It is based on the actual history of Caesar's assassination in 44 BC.
Though named after Caesar, with the plot revolving around his assassination, Brutus is the central character in Shakespeare's play. Much of the play focuses on the inner struggles of Brutus with the ethics and tensions of the situation in which the conspirators have involved themselves.
