A transition curve is provided on a circular curve on a highway to provide
1. Gradual introduction of centrifugal force
2. Minimum stopping sight distance
3. Gradual introduction of superelevation
4. Comfort and security to passenger
A. 1, 2 and 3
B. 1, 3 and 4
C. 2,3 and 4
D. 1, 2 and 4