In the neighbourhood of 0 the value of tan^2x lies between 0 to 1. So the GIF will be a constant value of 0
(Consider -pi/4 to pi/4 as the neighbourhood of 0) -pi/4 < x < pi/4 => -1 < tanx < 1 => 0 < tan^2 x < 1 => [tan^2 x] = 0
So it value is constant ie = => Continous => Limit Exists .
constant function is differentiable => f’(0)=0
so A is true , B is false as limit exists and equal to 0 , C is false as f’(0)=0, D is also false