I personally prefer A for the trunk lines, but you will have to play with the branches to make a more complete image. It gives me a slanting sort of vibe. Like growing in a valley where the winds blow through often.
B is pretty good as well as both the trunk lines and branches need less work to complete an image of the growing on a steep hill side. The far left tree looks out if place to me with that angle though. Mostly because it has so much movement compared to the other trunks.
C is my least preferred of the options, buy it does strike a good balance between A and B. Mostly in regards to the trunk lines having a more pronounced fanning effect.
I think C might look better if you tilt it at an angle (probably about half of B's tilt. Say 10 degrees or so.)