Google will help you a lot if you research
Roald Dahl's 'Lamb to the Slaughter' is a short story about the murder of police detective Patrick Maloney by his wife Mary. Driven to homicide after her husband's unexpected announcement that he's leaving her and their unborn child, Mary quickly regains her senses after fatally killing him with the leg of lamb.
Well, it's not A. Mary did not let hm accept the disease.
It's not B-he told her about his mother (I think).
It's not D because she is brought to live there.
It's C because she doesn't let him accept his illness and ends up helping him.