Answer:

IT'S OPTION 2 (NS)

Explanation:

CASE 1;

SPEED OF CAR =U M/S.

MINIMUM DISTANCE =S.

TIME=DISTANCE/SPEED=S/U.

NOW IT STOPS MEANS RETARDATION OCCURS,

SO,RETARDATION = -U×U/S=-U^2/S M/S^2.

CASE 2;

NOW SPEED BECOMES =nu.

TIME REMAINS SAME=S/U.

DISTANCE=SPEED×TIME =NU×S/U=NS.

RETARDATION = NEGATIVE of speed/time taken.

= -NU×U/NS= -U^2/S M/S^2

HERE IN BOTH CASES RETARDATION IS SAME MATE COZ TIME REMAINS SAME IN BOTH THE CASES. WELL THIS IS THE EXTRA ANSWER OF QUESTION YOU HAVE ASKED.

BUT ACCORDING TO QUESTION IN THE ATTACHMENT THE CORRECT OPTION IS B.