Correct option is A. 1,4,10,12
a. Area of v-t graph lies below the time axis, so displacement is negative, but slope is positive, so acceleration is positive.
b. Area of v-t graph lies above the time axis, so displacement is positive, and slope is positive, so acceleration is also positive.
c. Displacement is zero, because half area is above time axis and half below. Slope is negative, so acceleration is negative.
d. Area of v-t graph lies above the time axis, so displacement is positive, and slop is negative, so acceleration is also negative.