Final answer:
The variation of the 1/2 Kneeling Inline Row is the Iso split squat inline row, which adds a lower body stability challenge by incorporating an isometric split squat position while performing the row.
Step-by-step explanation:
The exercise that is a variation of the 1/2 Kneeling Inline Row is the B) Iso split squat inline row. This exercise combines the elements of a traditional inline row with the lower body stability challenge of an isometric split squat. During this exercise, you perform a one-arm row while maintaining the position of a split squat, which is beneficial for engaging the core and increasing unilateral strength.The 1/2 Kneeling Inline Row primarily targets the muscles of the back, specifically the latissimus dorsi, as well as the biceps, shoulders, and core. The Iso split squat inline row adds to this by involving the lower body more intensively, recruiting the glutes and thighs to sustain the split squat posture throughout the movement.