The radius of curvature of a plano - convex . lens is 20 cm If the refractive index of the material of the lens be $1.5$ it will

Question

$\begin{array}{1 1} \text{act as a convex lens only for the objects that lie on its curved side} \\ \text{act as a concave lens for the objects that lie on its curved side} \\ \text{act as a convex lens irrespective of the side on which the object lies } \\ \text{act as a convex lens irrespective of side on which the object lies }\end{array} $