Let $$\alpha, \beta, \gamma, \delta$$ be real numbers such that $$\alpha^2 + \beta^2 + \gamma^2 \neq 0$$ and $$\alpha + \beta = 1$$ Suppose the point (3,2,−1) is the mirror image of the point (1,0,−1) with respect to the plane $$\alpha x + \beta y + \gamma z = \delta$$. Then which of the following statements is/are TRUE?

A

$$\alpha + \beta = 2$$

B

$$\delta - \gamma = 3$$

C

$$\delta + \beta = 4$$

D

$$\alpha + \beta + \gamma = \delta$$