Which of the following statements is true regarding depletion?

• A. Depletion is the process of allocating the cost of intangible assets over their useful lives.
• B. Depletion is the process of allocating the cost of natural resources over their useful lives.
• C. Depletion is the process of allocating the cost of property, plant, and equipment over their useful lives.
• D. Depletion is the process of allocating the cost of inventory over their useful lives.
• E. All of the above