Which BB skill involves a 1/2 illusion turn at level 10?

The skill that involves a 1/2 illusion turn on the balance beam at level 10 is the BB illusion. This skill is characterized by the gymnast performing a turn while maintaining control and balance, utilizing an illusion turn technique where the body rotates in a way that creates the appearance of being in a more extended position. The 1/2 illusion turn is specific in that it requires the gymnast to smoothly transition from a standing position into the turn and back again, showcasing both strength and balance.

The wolf turn refers to a distinct skill that does not incorporate the illusion turn element. A gainer typically involves flipping backward off the beam, while a dismount refers to the final exit from the beam. These choices do not involve the combination of an illusion turn, which is central to the BB illusion skill. The BB illusion is thus the appropriate answer due to its technical requirements and execution specific to this type of turn.