Answer:
The manager's decision to have the menu revised suggests that she failed to
a. identify and diagnose the problem.
Step-by-step explanation:
As the manager couldn't understand the reason about the less number of customers in the evening. She devised a wrong plan to change the menu which was not the cause rather the services of wait staff was not good. So, the decision she made was not correct and the problem remained there as the number of customers didn't increased.
- All others options which states that she failed to evaluate alternatives or generate alternative solutions or evaluate the decision are all no correct in this situation as she would look for alternative if she could address the main problem. So the best answer is she failed to identify and diagnose the problem.