Which of the following is a lead-up skill related to the Yellow Stroke School?

The lead-up skill related to the Yellow Stroke School is lifting the head to breathe during pulsing. In the context of swim instruction, lead-up skills are foundational techniques that help swimmers progress toward the more complex skills they will eventually learn, like freestyle strokes. Lifting the head to breathe is crucial because it teaches timing and head positioning, which are vital for effective breathing in freestyle swimming. This skill allows swimmers to maintain their rhythm while also ensuring they can get air without disrupting their stroke flow.

In contrast, performing a freestyle flip turn, swimming backstroke with good body extension, and treading water are more advanced skills that typically come after mastering the foundational techniques, including proper breathing mechanics and body position in the water. Therefore, lifting the head to breathe is an essential element of instruction that facilitates smoother transitions into more complex swimming strokes and skills.