Answer:
Independence
Step-by-step explanation:
AICPA actually groups two rules together- Objectivity and Independence.
While it is very possible for both internal and external accountants to be Objective (impartiality and intellectually honest). Only an external accountant can be truly independent especially when providing auditing and other attestation services. These services are primarily performed to obtain an independent report or view of the financial state of an organisation.
Actually, it is clearly stated in the AICPA code of professional conduct that members or accountants not in public practice (internal accountants) cannot maintain an appearance of independence.
Every organisation's internal accountant is primarily responsible to the Board of Directors and Management of such an organisation.