Choice "D" is correct. When the prior period has been audited, the accountant should issue the current period compilation or review report, and any additional paragraph should indicate:

• That prior period statements were audited;

• The date of the previous report(s);

• The opinions expressed, and, if other than unmodified, the reasons for the modification; and

• That no auditing procedures have been performed since the previous report date.

Choice "b" is incorrect. The CPA would not mention control risk in the current period review report.Choice "a" is incorrect. There is no requirement that the reasons for the change be documented.
Choice "c" is incorrect. There is no requirement that the audit report no longer be relied upon.