Match each body to its best description:

1. Red giant: an old, very dense, hot star that is cooling
2. Nebula: a mass of gas and dust
3. Black hole: an object so dense that even light cannot escape its gravity
4. White dwarf: a large star that is relatively cool

So the correct match would be:

a) Red giant: an old, very dense, hot star that is cooling
b) Nebula: a mass of gas and dust
c) Black hole: an object so dense that even light cannot escape its gravity
d) White dwarf: a large star that is relatively cool