In modern foil fencing, a riposte (B in your example) gets the point. Also, the only way to get a hit is by thrusts to the torso. No other body parts count, and no slashing or cutting.
It's very interesting that modern fencing is so "ritualistic" and far removed from actual sword combat. I wonder how that happened?
I think that other weapons and combat forms pushed the sword to be limited to duels and mainly duels of honor. Fencing came from training to duel. The foil is a learning weapon and even though the entire torso is a target, most attacks ideally aim for the heart. Epee you really see the dueling roots. In epee many points are scored off your hand or foot. Duels of honor were commonly fought to first blood rather than death. First blood was typically a wound to the hand or other body part close to the action.
It's very interesting that modern fencing is so "ritualistic" and far removed from actual sword combat. I wonder how that happened?