Final answer:
The correct answer is A. True. Dentists are required by the Board to disclose the nature, extent, and cost of treatment to patients as part of their professional responsibility to ensure informed consent.
Step-by-step explanation:
It is indeed a rule of the Board that a dentist should disclose the nature and extent of the treatment needed by the patient, including the terms and conditions of the fee. The correct answer to the question is A. True. In the context of professional dentistry, it is essential that patients are fully informed of their treatment options, the potential risks involved, and the costs associated with the treatment. This is a matter of ethical practice and often a legal requirement, ensuring that patients can make informed decisions about their dental care. The disclosure of such information is part of the dentist's responsibility towards the patient.