I like C a lot. The double edge looks nicely implemented, and the tip looks like a good combination of piercing ability and strength. The convex grind for the top edge coupled with the flat grind for the bottom seems like a good way to maximize the effectiveness of each edge for its purpose, while maintaining good blade strength. Nice handle shape also, though as others have commented, I would like fewer pins. I like the hollow pins you used on A. Really a hardcore fighting knife.