Final answer:
A Red Blocker who initiates a whip to aid a Red Jammer while being half a lap behind the Pack in a game of roller derby will receive an Out of Play penalty, according to roller derby rules.
Step-by-step explanation:
The scenario described appears to be related to roller derby, a sport involving teams of skaters on a track. The question involves understanding roller derby rules, specifically those concerning penalties for actions considered Out of Play. When Red Blocker exits the Penalty Box and is half a lap behind the Pack, they are considered out of play until they reach the Pack. If the Red Blocker initiates a whip to help the Red Jammer gain speed, they would be involved in play while still out of play by the rules, and thus they should receive an Out of Play penalty. The correct choice, in this case, would be A. Red Blocker, as they initiated the whip while being out of play (half a lap behind the Pack).