The correct option is C 68 m/s2
As we know that the acceleration of the particle is given by
a=dvdt and also, v=dxdt
Given, x=3t3−2t2+5
So, v=dxdt=d(3t3−2t2+5)dt
⇒ v=9t2−4t
also, a=dvdt=d(9t2−4t)dt=18t−4
Thus, the acceleration of the particle is 18×4−4=68 m/s2