If B1 makes contact with a pitched ball while leaning entirely outside the box, what happens?

When B1 makes contact with a pitched ball while leaning entirely outside of the batter's box, the correct outcome is that B1 is out for being out of the box. In baseball, a batter must be within the confines of the batter’s box when hitting the ball. If the batter has their entire body outside the box at the moment of contact, it is considered a violation of the rules, resulting in an out.

This ruling reinforces the importance of maintaining the designated area during a hit and prevents any unfair advantage that may arise from hitting the ball while positioned outside the batter’s box. The other choices suggest scenarios that do not apply in this context, where being completely out of the box at the point of contact directly leads to the batter's out status.