Choice "B" is correct. With respect to events occurring after the issuance of an auditor's report, the auditor is only responsible for information that existed at the audit report date.
Choice "a" is incorrect. Since the information did not exist at the report date, the auditor has no obligation to make any further inquiry.
Choice "d" is incorrect. Since the information did not exist at the report date, the auditor has no obligation to make any further inquiry.
Choice "c" is incorrect. Since the information did not exist at the report date, the auditor has no obligation to make any further inquiry.