Which players are considered "in the free blocking zone" at the snap?

The correct answer highlights that a player is considered "in the free blocking zone" at the snap if any part of their body is within that designated zone. The free blocking zone is specifically defined as the area between the two offensive tackles and extends one yard on either side of the line of scrimmage. This rule allows for certain types of blocks without the constraints typical to blocking rules applied to all players, thereby allowing more aggressive play in this area.

When any player has part of their body within the boundaries of the free blocking zone at the moment of the snap, they are subject to the rules and allowances that pertain to that zone. This means both offensive and defensive players can engage in blocking maneuvers without drawing certain penalties that would apply outside this area. This significant clarification helps in understanding game dynamics, especially during the initial phases of the play.

The other options do not accurately encapsulate the role of players in the free blocking zone. Limiting it only to offensive linemen or defensive players does not reflect the rule's intent, as it aims to include any player positioned in the zone. Mentioning players on the sidelines is irrelevant, as they are not part of the play and thus cannot be considered in the free blocking zone.