Nebulae are large clouds of dust and gas that may eventually form stars and planets. Astronomers originally thought that the Andromeda Galaxy was a nebula until the nature of a galaxy was confirmed. Which of the following shows the relationship between a galaxy and a nebula? A. Many galaxies are found inside of a single nebula.
B. Entire galaxies are created from the gas and dust of a single nebula.

C. Many nebulae are found inside of a single galaxy. D. Nebulae and galaxies combine to form stars.