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Which one of the following is equivalent to ${(-y)}^{-2}-{x}^{2}$ ?

${(y)}^{2}-{x}^{2}$

$\cfrac{1-{x}^{2}}{y^{2}}$

$\cfrac{{y}^{2}-{x}}{y^{2}}$

$\cfrac{{1-{x}^{2}y}^{2}}{y^{2}}$

$\cfrac{{y^{2}-{x}^{2}y}}{y^{2}}$