Reflecting on whether a adding a salad bar to a school lunch menu fixed a problem is an example of EVALUATING A SOLUTION.
For every decision that one makes, there is a need to consider the pros and the cons of the decision in order to ensure that resources are used judiciously. When a problem has been identify and solved, there still remains a need to check whether the solution used effectively take care of the problem, this is what is called evaluation.
In the question given above, considering whether adding a salad bar to the school menu fixed a problem is an example of evaluating a solution.