IRB Law 21.4 (a) Scrum alternative. A team awarded a penalty or free kick may choose a scrum instead. They throw in the ball. Opps -- you mean calling a mark. Then Law 18.6 (a) applies. "The team of the player who made the mark may choose to take a scrum." So yes -- the player has that option. And if the kick is taken, it is considered a free kick.
BLM is quite correct but why would a team have a scrum from a mark when a mark can only be awarded inside your own quarter. Not like the old days when marks could be taken anywhere and players could even kick for goal from a mark.
