A. the idiom is - It's a piece of cake.
B. the idiom is - It sells like hot cakes.
C. the idiom is - You can't have your cake and eat it.
D. the idiom is - Icing on the cake.
1) Her new book is selling like hot cakes.
2) And the ring is just the icing on the cake.
3) That job was a a piece of cake. It was the easiest thing that I ever did.
4) You want to spend your money and still have it. You can't have your cake and eat it too!
