For a regular polygon, let r and R be the radii of the inscribed and the circumscribed circles. A false statement among the following is

Question

$\begin {array} {1 1} (A)\;there \: is \: a \: regular\: polygon\: with\: \large\frac{r}{R}=\large\frac{1}{2} \\ (B)\;there\: is\: a \: regular\: polygon\: with\: \large\frac{ r}{R} =\large\frac{1}{\sqrt 2} \\ (C)\;there\: is\: a\: regular\: polygon \: with \: \large\frac{r}{R}=\large\frac{2}{3} \\ (D)\;there\: is\: a\: regular\: polygon \: with\: \large\frac{ r}{R}=\large\frac{ \sqrt3}{2} \end {array}$