Which of the following statements is true?

(a) Depreciation and amortization represent the cost of assets other than land that will benefit a business enterprise for less than a year.

(b) Repair and maintenance are the annual costs of repairing and maintaining the firm’s property, plant, and equipment.

(c) Impairment charges are the expenses recognized to record an increase in value of a long-term asset.

(d) Accounting rules permit only one different method to account for stock investments of less than 50%.