Can a back break the plane of the waist of a lineman?

A back can indeed break the plane of the waist of a lineman, specifically when positioned behind the player who is under the snapper. This situation occurs because the rules permit a specific action where a back, during a play, can move past the line of scrimmage, which in most cases involves the area near the linemen.

This allowance is critical for legitimate offensive plays, as it helps create space and options for running or passing the ball. The rules do stipulate that this action should occur with the understanding that positional integrity must be maintained, meaning the game recognizes the dynamics of the line and the backs’ position in relation to it. Therefore, it’s essential to understand the context of allowed movements and the strategic implications in gameplay.

Considering why the other options don't hold: stating it's entirely against the rules fails to recognize this nuanced allowance, while suggesting that backs can break the plane without restriction ignores the importance of positional context in the rules. The mention of "special circumstances" implies an inconsistency with the general rules that apply to most plays.