Scratching, though a useful self-remedy for an occasional itch, can _______ a problem by damaging the skin if performed too _______.
Since scratching worsens wounds, as intended in "Scratching...problems" by doing it intensely, as intended in “if performed too...” the contextual synonym for worsen would be exacerbate and for intensely would be vigorously. Hence, Option A is correct. The rest of the options do not express the antonym, hence, incorrect.