From the AP Physics 1 Essentials book... a tricky question.
For B, because you're passing through the zero point, you find the energy going from 3 m/s to 0 m/s, and then the energy going from 0 m/s to -3 m/s, and add them. Same idea with D. It requires you to think past the standard definition and understand what sort of work must be done to accomplish the feat.