Since a left handed receiver is likely to return the ball with his forehand, he will be using a stroke that is more comfortable to handle the sidespin on the serve. This, coupled with the fact that the normal stroke of the left hander is crosscourt, will tend to push the normal landing area of the return a little more to the server's left than for a right handed receiver, although it should still be more to the right than for a forehand serve. Player A will need to stand not quite so far to the right in order to compensate for this.
This backhand serving tactic is not quite as effective against left handers, although when combined with a forehand serve that crosses the receiver's playing elbow from left to right it can still be a very useful strategy.