Transition curves are introduced at either end of a circular curve, to obtain

Question: Transition curves are introduced at either end of a circular curve, to obtain

1.gradually decrease of curvature from zero at the tangent point to the specified quantity at the junction of the transition curve with main curve

2.gradual increase of super-elevation from zero at the tangent point to the specified amount at the junction of the transition curve with main curve

3.gradual change of gradient from zero at the tangent point to the specified amount at the junction of the transition curve with main curve

4.none of these.

Answer:2