If It Is Found That an Error Had Been Made

If it is found that an error had been made in a prior period:

A) The error should be rectified by including the item of income or expense in the period in which the error was discovered.
B) IAS 1 does not cover this concept and so no entry is required.
C) IAS 8 requires that errors are corrected via an adjustment to opening balance of retained earnings.
D) Material errors discovered in the current reporting period must be included in that period's statement of comprehensive income, while non-material errors may be corrected with an adjustment to opening retained earnings.