What happens if a player plays a bowl that touches the jack without realizing it?

When a player plays a bowl that touches the jack, that bowl is indeed marked as a toucher. This designation is significant in the game of bowls because touchers gain special status and are considered to be "alive," meaning they remain in play even if they go out of bounds.

The rules dictate that once a bowl touches the jack, it must be marked with a special chalk or marker, indicating its status as a toucher. This allows players to clearly identify which bowls are valid for scoring and ensures the game's integrity. In the context of the options provided, marking the bowl as a toucher is the correct response, as it reflects the rules and practices upheld in the sport.

The implications for the other options are that a bowl that touches the jack does not get removed or negate the player's turn. Additionally, there is no loss of the round or foul simply because the player was unaware that the bowl touched the jack; the play continues with that bowl counted among the valid ones.