If a = \(\frac{2x}{1 - x}\) and b = \(\frac{1 + x}{1 - x}\), then a2 - b2 in the simplest form is
A
\(\frac{3x + 1}{x - 1}\)
B
\(\frac{3x^2 - 1}{(x - 1)}\)2
C
x\(\frac{3x - 2}{1 - x}\)
D
\(\frac{3x^2 - 1}{(x - 1)}\)