Choice "A" is correct. The benefits of a financial expert on the audit committee relate to the expertise that the board can bring to its oversight function.
Choice "b" is incorrect. The audit committee provides oversight of the annual audit; however, the audit committee and its financial expert do not verify the auditor's work.
Choice "d" is incorrect. The term "expert" within the context of the Sarbanes-Oxley Act does not convey the same requirements as SEC regulations and does not convey either a higher level of due diligence or provide insulation to other board members. The Act is silent as to the meaning of expert outside of the qualifications to be deemed an expert.
Choice "c" is incorrect. The financial expert does not certify compliance with SEC regulations.