JEE Mains (Friction)

A block of mass m is placed on a surface with a vertical cross-section given by y =x³/ 6. If the coefficient of friction is 0.5, the maximum height above the ground at which the block can be placed without slipping is

(a) ⅓ m

(b) ½ m

(c) ⅙ m

(d) ⅔ m