Option 1 -> Precocious means showing advanced development or maturity at an early age, not related to professional status.
Option 2 -> Professional refers to someone skilled and paid for their expertise, the direct opposite of amateur.
Option 3 -> Dilettante means someone who dabbles casually in an activity, actually similar to amateur.
Option 4 -> Perfectionist describes someone who seeks perfection, which can apply to both amateurs and professionals.
Hence, Option 2: Professional -> An amateur engages in activities for pleasure without formal training or payment, while a professional is skilled, trained, and typically compensated for their work, making them direct antonyms -> correct