An audit of historical financial statements is a form of: Select one: a. attestation service in which the auditor issues a written report expressing an opinion about whether the financial statements are in material conformity with auditing standards. b. assurance service in which the auditor issues a written report expressing an opinion about whether the financial statements are in material conformity with auditing standards. c. none of the above. d. attestation service in which the auditor issues a written report expressing an opinion about whether the financial statements are in material conformity with accounting standards. An auditor assesses the level of control risk to: Select one: a. determine whether the entity is a going concern. b. determine the extent of substantive tests to be performed. c. ascertain whether irregularities are probable. d. ascertain whether any employees have incompatible duties