If x + y = 2a, then the value of ax - a + ay - a is?

Answer: Option A

$$\begin{array}{rl}& \text{Given, }x+y=2a\\ & \text{Find, }\frac{a}{x-a}+\frac{a}{y-a}\text{ = ?}\\ & \underset{3}{\underset{\downarrow }{x}}+\underset{1}{\underset{\downarrow }{y}}=\underset{2}{\underset{\downarrow }{2a}}\\ & \text{Let }x=3,y=1,a=2\\ & \therefore \frac{a}{x-a}+\frac{a}{y-a}\\ & =\frac{2}{\left(3-2\right)}+\frac{2}{\left(1-2\right)}\\ & =\frac{2}{1}+\frac{2}{-1}\\ & =0\end{array}$$