Jacob received his score on his math paper and realized that he performed poorly. According to the steps in problem solving, the next step that must be taken by him is to

According to the steps in problem-solving, the next step that must be taken by him is to: rethink and redefine his problem

After receiving the result, Jacob should introspect himself and find out why and how his poor performance happen. After figuring out what cause his poor performance, he had to do a vigorous effort to make it go away and change his habits.