[Zaltar Zeb] Zeb Suffers from Delusions That He Is from the Planet

[Zaltar Zeb] Zeb suffers from delusions that he is from the planet Zaltar. Zeb's contract with DigiTV, his digital television service provider, has expired. After comparing his past payments to the potential savings from satellite television provider SatTV, Zeb decides to sign a two-year contract with SatTV. After six months with SatTV, Zeb realizes he paid less with DigiTV and he now wants to be released from his contract with SatTV.
-If a court has declared Zeb insane and his sister is appointed guardian, which of the following statements would be true?

A) Zeb's sister has the sole legal capacity to enter into contracts on Zeb's behalf and any contract Zeb enters into is void.
B) Zeb's sister may enter into contracts on Zeb's behalf, but only with Zeb's affirmance.
C) Both Zeb and his sister have capacity to enter into contracts, however, any contract Zeb enters into may be disaffirmed by Zeb.
D) Zeb may enter into contracts, but they may be disaffirmed by his sister.
E) Zeb may enter into contracts, but they are voidable by his sister.