On January 2, 2021, Ross Co. purchased a machine for $500. This machine has a 4-year useful life, a residual value of $100, and is depreciated using the straight-line method for financial statement purposes. For tax purposes, depreciation expense was $200 per year for 2021 and 2022. The company's tax rate is 21% in 2021 and 2022 but will be 28% in 2023 and 2024.

How much deferred tax liability should the company record in 2021?

A. -21

B. 28

C. 7

D, 21