The correct answer is: B. Successful serve that the opponent fails to touch.
An ace in tennis is a serve that the opponent fails to return. It is the most difficult shot to return in tennis, and it is often the deciding factor in a point.
A double fault is when a player serves two consecutive faults. A fault is when the ball does not land in the service box.
A situation when the ball has landed up is called a let. A let is a serve that is not a fault, but that is not good enough to be considered a serve.
A state of score when either party must gain two consecutive points to win the game is called deuce. Deuce occurs when the score is tied at 40-all. To win a game at deuce, a player must win two consecutive points.
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