C and D are true. To solve, just factor out the common terms by dividing the polynomial. A would be 3m(5m^2-2) and is wrong as the 6m was not divided by 3m. B would be 6m(m+3) and is wrong as you can only factor out one m as they only share one m.
I'm assuming you mean

we can factor that sum of perfect cubes from

into

so therefor

that is simpliest form
You'll set the two expressions equal to 95.
So 2x+119=95
Then 2x=-24
Finally x=-12