A and D.
A slight different than most but i like the idea of Karmic Revange. Someone tries to transforms someone else and gets transformed in the process him/herself.
A nice example
http://doc.furvect.com/Stories/Adobeman10/trading.html
Woman turns her pet-pig into a human and when she tries to reverses it she gets transfomed into a pig herself and ends as the former pigs pet.