All stars have the following stages in common in their life cycles:
- Nebula: This is the initial stage where stars form from clouds of gas and dust.
- Protostar: This is the stage where the nebula begins to collapse under gravity, forming a protostar as it heats up.
- Main Sequence: After the protostar stage, stars enter the main sequence phase, where they spend most of their lives fusing hydrogen into helium.
The stages "white dwarf" and "black hole" are not common to all stars; they depend on a star's mass. Therefore, the response that reflects common stages among all stars would include "nebula" and "protostar."