Which of the following is a conceptual difference between the attestation standards and generally accepted auditing standards?

a. The attestation standards do not apply to audits of historical financial statements, while the generally accepted auditing standards do.

b. The requirement that the practitioner be independent in mental attitude is omitted from the attestation standards.

c. The attestation standards do not permit an attest engagement to be part of a business acquisition study or a feasibility study.

d. None of the standards of fieldwork in generally accepted auditing standards are included in the attestation standards.