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Which one of the following is the correct form of the decomposition of the rational expression : $\cfrac{2x^{2} + 1}{x^{4}- 1}$?

$\cfrac{A}{x - 1}$ + $\cfrac{B}{x + 1}$ + $\cfrac{Cx + D}{x^{2} + 1}$

$\cfrac{A}{x - 1}$ + $\cfrac{B}{x - 1}$ + $\cfrac{Cx + D}{x^{2} + 1}$

$\cfrac{A}{x - 1}$ + $\cfrac{B}{x + 1}$ + $\cfrac{C}{x^{2} + 1}$

$\cfrac{Ax + B}{x^{2} - 1}$ + $\cfrac{Cx + D}{x^{2} + 1}$