Which of the following option correctly describes the variation of...

$\text{a} = \text{(g} - \alpha \text{v)}$

$\dfrac{\text{dv}}{\text{dt}} =$$\text{g} - \alpha \text{v}$

$\mathop{∫}_{0}^{\text{v}}\dfrac{\text{dv}}{\text{g} - \alpha\text{v}} = \mathop{∫}_{0}^{\text{t}}\text{dt} ⇒ ℓ\text{n}\left(\dfrac{\text{g} - \alpha\text{v}}{\text{g}}\right) = - \alpha\text{t}$

$v = {\text{v}}_{0}\left(1 - {\text{e}}^{- \alpha\text{t}}\right)\text{a} = \dfrac{\text{dv}}{\text{dt}} = {\text{v}}_{0}\alpha{\text{e}}^{- \alpha\text{t}} = {\text{a}}_{0}{\text{e}}^{- \alpha\text{t}}$