[Solved] Which of the following chromosomal disorders does not involve abnormal sex chromosomes? A) Turner's syndrome B) XXX syndrome C) Down syndrome D) Klinefelter's syndrome Avoidable Costs: Expenses that can be eliminated if a particular decision is made or if an activity is ceased. Sunk Costs: Costs that have already been incurred and cannot be recovered, and should not affect future business decisions. Irrelevant Costs: Costs that will not be affected by a decision and should not be considered when making that decision. Periodic Basis: A method of accounting where financial and inventory records are updated at regular, fixed intervals.