Final answer:
The Stability ball leg curl is a variation of the Slideboard Leg Curl Eccentrics, utilizing a stability ball to engage the hamstrings and glutes.
Step-by-step explanation:
The exercise that is a variation of the Slideboard Leg Curl Eccentrics is A) Stability ball leg curl. This variation uses a stability ball instead of a sideboard to target the hamstrings and glutes. The user lies on their back, places their feet on the ball, lifts their hips off the ground, and curls the ball towards their body by bending the knees while maintaining hip elevation. This exercise emphasizes the eccentric motion when the user slowly returns to the starting position, similar to the Slideboard Leg Curl Eccentrics.