What action is taken if B8 bats instead of B7 and the error is detected after two strikes?

When B8 bats in place of B7 and the error is realized after two strikes, the ruling maintains the integrity of fair play while acknowledging the circumstances surrounding the situation. The correct choice allows for B7 to take B8's place without penalty. The reason for this is rooted in the fundamental rules governing proper player substitutions and at-bats.

In baseball, if a player bats improperly, and it is discovered, a correction can be made if it occurs before the conclusion of that at-bat. Since the substitution happened before the third strike, B7 can step in to rectify the scenario. This action is in line with maintaining the fairness of the game—B8's right to bat is nullified, and B7 is reinstated to complete the at-bat, ensuring that the team is represented correctly.

The other possible outcomes, such as allowing B8 to continue batting or declaring B8 out immediately, would complicate the game's fairness and potentially disadvantage one team without an appropriate error resolution method. Continuing without changes would also disregard the mistake, which could undermine the game's structure.