Answer:
Nebular
Step-by-step explanation: Galaxy is a system of stellar remnants, stars, dust, gas and dark matter, held together by gravitational attraction. Galaxies are classified as elliptical, spiral or irregular on the basis of visual structure.
Nebula is a part of galaxy where new stars and planetary systems are formed. It is a cloud of dust and gas. It may come from the explosion of dying stars, for example supernova.