As Part of an Audit,a CPA Often Requests a Representation

As part of an audit,a CPA often requests a representation letter from the client.Which one of the following is not a valid purpose of such a letter?

A) To provide audit evidence.
B) To emphasize to the client their responsibility for the fairness of the financial statements.
C) To satisfy himself or herself that a certain account balance is fairly stated when certain customary auditing procedures are not performed.
D) To provide possible protection to the CPA against a charge of knowledge in cases where fraud is subsequently discovered to have existed in the accounts.