Which of the following is not an AICPA general standard for attestation engagements?

a. The practitioner must have adequate technical training and proficiency to perform the attestation engagement.
b. The practitioner must have reason to believe that the subject matter is capable of evaluation against criteria that are suitable and available to users.
c. The practitioner must adequately plan the work and must properly supervise any assistants.
d. The practitioner must exercise due professional care in the planning and performance of the engagement and the preparation of the report.

c