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Q)

If $^nC_r$ denotes the number of combinations of $n$ things taken $r$ at a time, then the expression $^nC_{r+1} + ^nC_{r-1} + 2 \times ^nC_r$ equals :


( A ) $^{n+1}C_{r}$
( B ) $^{n+1}C_{r+1}$
( C ) $^{n+2}C_{r+1}$
( D ) $^{n+2}C_{r}$

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