The most widely-used depreciation method for U.S.income tax purposes is

A) sum-of-the-years' digits.
B) MACRS.
C) straight-line.
D) units-of-production.

MACRS (Modified Accelerated Cost Recovery System) is the most widely-used depreciation method for U.S. income tax purposes. It allows for accelerated depreciation of assets over several years and is preferred by most businesses because it results in greater tax deductions in the early years of an asset's useful life. Sum-of-the-years' digits, straight-line, and units-of-production are also common depreciation methods, but they are not as widely used for income tax purposes as MACRS.