Let $X$ be a set containing $n$ elements. If two subsets $A$ and $B$ of $X$ are picked at random, the probability that $A$ and $B$ have the same number of elements, is
Let $X$ be a set containing $n$ elements. If two subsets $A$ and $B$ of $X$ are picked at random, the probability that $A$ and $B$ have the same number of elements, is
- A
$\frac{{^{2n}{C_n}}}{{{2^{2n}}}}$
- B
$\frac{1}{{^{2n}{C_n}}}$
- C
$\frac{{1\,.\,3\,.\,5......(2n - 1)}}{{{2^n}}}$
- D
$\frac{{{3^n}}}{{{4^n}}}$
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