Which sentence contains an unlike comparison of items?

A) Andy's homework for algebra seemed much harder than Angela's homework for the same class.
B) While Amelia's carnations are quite lovely, the soil used for Mrs. Sadie's plants is much richer.
C) Martha was sure that her spaniel shed much more fur than her friend Mary's spaniel did.
D) At the car show, the red Mustang ended up fetching a much higher price than the mint-green Mustang.