Final answer:
The client needs further instructions regarding keeping the hearing aid on at all times for better results.
Step-by-step explanation:
The correct statement that indicates a need for further instructions is b. The hearing aid should be on at all times for better results. This statement is incorrect because the client should be instructed to turn off the hearing aid when it's not being used. Keeping the hearing aid on at all times can drain the battery faster and may not be comfortable for the client. It's important to conserve the battery life and ensure the client's comfort.