When a pitcher is penalized for a balk with runners on base, what happens to the bases?

In the context of baseball rules regarding balks, when a pitcher is penalized for a balk with runners on base, the appropriate ruling is that each runner advances one base. This rule is designed to prevent the pitcher from gaining an unfair advantage over the baserunners.

When a balk is called, it indicates that the pitcher has committed an illegal motion that potentially disrupts the rhythm of the game or the baserunners' movements. The penalty reflects a balance between the offense's right to advance and the need for the pitcher to adhere to the rules of pitching. Awarding each runner one base allows them to move forward, reflecting the recognition of the breach, while maintaining the integrity of the game's structure.

This ruling contrasts with other options, which suggest different outcomes such as no advancement, an award of two bases, or returning to original positions—all of which do not align with the established rules surrounding balks in baseball.