Study the following statements and identify the correct combinations of statements.

Statements:

(A) A transition curve is a horizontal curve having a variable radius i.e., infinity at the tangential point to the selected radius of the horizontal curve.

(B) A transition curve connecting a straight road and a vertical curve on either side of a turn.

(c) Centrifugal force is the main cause of the jerk due to the sudden transition experienced while transitioning a horizontal curve

(D) As the transition curve has an infinite radius at starting tangential point the Centripetal force at that point is zero. Thereafter the radius of the transition curve decreases gradually which in turn increases the Centripetal force gradually without any jerk.