Sum of n terms of series $(n^2-1^2)$ + $2\;.(n^2-2^2)$ + $3\;.(n^2-3^2)$+.....is

Question

$(a)\;0\qquad(b)\;2n\;(n^2-1)\qquad(c)\;\frac{1}{4}\;n^2\;(n^2-1)\qquad(d)\;\frac{1}{4}\;n\;(n+1)^2$