Answer:
d. She is discharged from performance because of impossibility of performance.
Step-by-step explanation:
Alice's refusal to keep Creaky and Toady can be based on fact that She is discharged from performance because of impossibility of performance. Discharge of contract by impossibility of performance usually occurs when the contractual duty cannot be performed due to unforeseen and uncontrollable circumstances, such as death, illness etc, which can lead to the party been released from a contract on the ground that such uncontrollable circumstances have rendered performance impossible.