Wow...what a thread.
1) I'm surprised at those of you who are going to give B the ball for a throw-in,
2) No, the hand is not part of the ball...buuuutttt..the rule exception essentially lets us treat it as such WHEN the defender is making a legitimate play on the ball. That rule rewards the defense, great. Now if I make a play on the ball and incidentally hit the hand, which is actually the ball, and the ball goes out of bounds, I have caused the ball to go out of bounds, period. A's ball for the ensuing throw-in.