question_answer

If the variable takes values 0, 1, 2, 3, ...... n with frequencies proportional to \[{}^{n}{{C}_{0}},{}^{n}{{C}_{1}},\]\[{}^{n}{{C}_{2}},.....{}^{n}{{C}_{n}}\] respectively, then the variance is

A)  \[\frac{n}{4}\]             

B)  \[\frac{n}{3}\]           

C)  \[\frac{2n}{5}\]           

D)  None of these