A ball is dropping in 3 different ways
(a) X-i, Y- ii, Z-iii
(b) X-ii, Y-i, Z-iii
(c) X-ii, Y-iii, Z-i
(d) X-iii, Y-ii, Z-i
Simple concept steeper the path greater the velocity.
The starting slope for the ball in X is steepest. So, acceleration is more therefore slope of the graph v/t in the starting will be maximum. So, for X is ii.
Y and Z alomost identical, but for Z the section before the flat region is longer. So it is going to taken a longer to reach constant velocity. In graph iii we see that the time taken by the ball to reach constant velocity is higher. So, for Z the correct graph is iii. The remaining is for y