Which type of wave does not require a medium to travel through? A. rope wave B. radio wave C. slinky wave D. tuning fork wave

The answer is radio wave, waves on the electromagnetic spectrum don't need a medium

For three of the four, you have named the medium ... rope, slinky, and

tuning fork. In each case, there would be no wave without it.

The radio wave, as well as all other electromagnetic waves, can travel

through material media, but don't need one in order to propagate.