Correct Answer - C
`U=2-20x+5x^(2)`
`F=-(dU)/(dx)=20-10 x `
At equilibrium position , F=0
`20-10 x=0`
`rArr x=2`
Since particle is released at x=-3, therefore amplitude of particle is 5.
It will oscillate about x=2 with an amplitude of 5.
`:. ` maximum value of x will be 7.