JEE Math Practice Question

Let $$A = \left[ {\begin{matrix} 1 & 2 \\ { - 1} & 4 \\ \end{matrix} } \right]$$. If A$$-$$1 = $$\alpha$$I + $$\beta$$A, $$\alpha$$, $$\beta$$ $$\in$$ R, I is a 2 $$\times$$ 2 identity matrix then 4($$\alpha$$ $$-$$ $$\beta$$) is equal to :

1. A.5
2. B.$${8 \over 3}$$
3. C.2
4. D.4