This word means the same as the given italicized word. Hence option C is correct.
Option A: 'Subtle' means 'delicately complex, difficult to describe'.
Option B: 'Clear' means 'easy to understand or see'.
Option D: 'Slow' means 'moving at a low speed, not quick'.
Option E: 'Arrhythmic' means 'without rhythm or regularity'.
These words do not mean the same as the given word 'nimble'.
So, options A, B, D and E are wrong.