JEE Math Practice Question

Consider : f $$\left( x \right) = {\tan ^{ - 1}}\left( {\sqrt {{{1 + \sin x} \over {1 - \sin x}}} } \right),x \in \left( {0,{\pi \over 2}} \right).$$ A normal to $$y = $$ f$$\left( x \right)$$ at $$x = {\pi \over 6}$$ also passes through the point:

1. A.$$\left( {{\pi \over 6},0} \right)$$
2. B.$$\left( {{\pi \over 4},0} \right)$$
3. C.$$(0,0)$$
4. D.$$\left( {0,{{2\pi } \over 3}} \right)$$