Option 1 -> Contract means to decrease in size or make smaller, not directly opposite to detract.
Option 2 -> Restrain means to hold back or limit, which doesn't oppose the meaning of detract.
Option 3 -> Enhance means to improve or increase the value/quality of something, directly opposite to detract (which means to diminish or take away from value).
Option 4 -> Conform means to comply with standards or rules, unrelated to detract.
Hence, Option 3: Enhance -> DETRACT means to reduce or take away value from something, while ENHANCE means to add value or improve something, making them perfect antonyms -> correct