Henry Hires Ace Roofing to Put a New Roof on His

Henry hires Ace Roofing to put a new roof on his house.When Ace comes,Henry refuses to let them on the roof,saying that he has a headache and doesn't want to listen to pounding.The next day,Henry still has a headache and he refuses to allow them on the roof.The day after,the baby is sleeping and Henry refuses to allow them to work.After four weeks of this,Ace:

A) may be discharged,but Henry is not.
B) may be discharged,and so would Henry.
C) can sue for damages,but must perform when Henry is ready.
D) has no choice but to keep coming back each day until Henry is ready.