In the reversible reaction 2NO₂ ⇌ᵏ¹ N₂O₄, the rate of disappearance of NO₂ is equal to:

A. 2k₁₂/k₋₁ [NO₂]²
B. 2k₁₋ [NO₂]² - 2k₋₁ [N₂ O₄]
C. (2k₁ - k₋₁) [NO₂]
D. 2k₁ [NO₂]² - k₋₁ [N₂ O₄]