Choice "A" is correct. The introductory paragraph of the standard unmodified report includes a statement that the financial statements are the responsibility of the company's management. Management's refusal to accept responsibility for the fair presentation of the financial statements therefore precludes issuance of this standard report.
Choices "c" is incorrect. Preventing the review of documentation of the predecessor auditor would be a reason not to accept the engagement. Choices "d", and "b" are incorrect, as there are generally alternative procedures the auditor can perform to accomplish his or her goals.