Think of it as a power-to weight ratio, Sam.
A is powerful, but weighs a tonne. Sort of like an American V8 truck.
C is light, but not very powerful. Sort of like a 2CV.
B is light and almost as powerful as A. Certainly more so than C.
If you're going camping and carrying your gear by bike, you want a light stove. Some can be shockingly light, but as is the way with all gear, fewer grams cost more squids...