Answer:
A. Malvolio has gone mad.
Step-by-step explanation:
In Shakespeare's "Twelfth Night," countess Olivia's steward, Malvolio, is made believe that his affluent master is in love with him. Thus, he receives a fake letter which makes him wear yellow stockings and cross-garters, be rude to the rest of the servants and smile in Olivia's presence. As a result, Olivia believes he has lost his mind and leaves him under responsibility of his harassers Sir Toby, Sir Andrew and Maria, who lock him in a dark chamber.