The sum of all the products of the first \[n\] natural numbers taken t

1.	The sum of all the products of the first \[n\] natural numbers taken two at a time is
A.	\[\frac{1}{24}n(n-1)(n+1)(3n+2)\]
B.	\[\frac{{{n}^{2}}}{48}(n-1)(n-2)\]
C.	\[\frac{1}{6}n(n+1)(n+2)(n+5)\]
D.	None of these
Answer» B. \[\frac{{{n}^{2}}}{48}(n-1)(n-2)\]

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The sum of all the products of the first \[n\] natural numbers taken two at a time is

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