The correct answer is A. Reply.
A reply is a response to a question or statement. A solution is a means of solving a problem. An answer is a response to a question. A resolution is a formal decision or determination.
A problem is a situation that is difficult or troublesome. A reply is a response to a question or statement. A solution is a means of solving a problem. An answer is a response to a question. A resolution is a formal decision or determination.
In the context of the question, the antonym of problem is reply. This is because a reply is a response to a question or
statement, while a problem is a situation that is difficult or troublesome.The other options are not antonyms of problem. A solution is a means of solving a problem. An answer is a response to a question. A resolution is a formal decision or determination.