Astronomers use many different pieces of equipment to study space: optical telescopes on Earth, space telescopes, and space probes are a few. Why would astronomers use a space probe instead of a telescope?

AProbes send back much better images than telescope.
BProbes are travel through space faster than light.
CProbes can take scientists to other planets; telescopes cannot.

Eliminate

DProbes send data back to Earth for scientists to study, not just images.