The correct answer is: A. confound
Moments of solitude and silence help the poet to concentrate on his poetic combination. This is because solitude and silence provide a quiet and peaceful environment that is conducive to concentration. In contrast, confound, disturb, and distract are all words that suggest that something is making it difficult to concentrate.
Confound means to confuse or bewilder. Disturb means to make someone feel agitated or restless. Distract means to draw someone’s attention away from something.
In the context of the question, it is clear that the poet is trying to concentrate on his poetic combination. Therefore, the only word that makes sense is confound. The other words would all make it more difficult for the poet to concentrate.