Final answer:
If a ball falls off the tee before a golfer's forward swing, they can replace it without penalty.
Step-by-step explanation:
In golf, if a ball falls off the tee before a player has taken their forward swing, they are allowed to replace it.
According to the Rules of Golf, when a ball is in play on the teeing ground, a player is allowed to tee it up again without penalty if it falls off or is knocked off the tee before the player has made a stroke at it. However, once the player has taken their forward swing and the ball has been set in motion, they cannot replace it.
For example, if a golfer addresses the ball, but the ball falls off the tee before they swing, they can place the ball back on the tee and continue without penalty.