Golf Rule 3

Stroke Play

STROKE PLAY: the winner of stroke play competition is the player who takes the fewest amount of strokes for a stipulated round or rounds.
NOTE--a player must hole out at every hole. A player receives a DISQUALIFICATION PENALTY if he fails to hole out on any hole and doesn't correct his mistake before playing a stroke from the next teeing ground. or in the case of the last hole of the stipulated round, before he leaves the putting green.

DOUBT AS TO CORRECT PROCEDURE: only in stroke play may a player play a second ball if he doubtful of his procedure, options, or rights. The player's first step is to announce his decision to invoke this rule to his marker or a fellow competitor, and which ball he would like to count if the rules permit.
NOTE--the player must, I repeat, must, report all the facts to the Committee before returning his score card, unless he scores the same with both balls. If he doesn't report the facts when he is required to, a DISQUALIFICATION penalty results.

DETERMINATION OF SCORE: the player must count the score selected in advance if the rules allow that selection. If the player does not announce in advance which ball he would like to score with, he is required to score with the original ball. If the original ball is not one of the balls played, the first ball the player put into play must count if the rules allow.
NOTE--a scond ball is not the same as a provisional ball.
NOTE--the general penalty for a rule violation in stroke play is two strokes unless otherwise provided.
NOTE--disqualification is the penalty for a competitor who refuses to comply with rights of another competitor.