Which is the correct sequence in the life cycle of an average star?

The sequence of "Nebula -> protostar -> main sequence star -> red giant" accurately describes the life cycle of an average star, particularly one like our Sun. The process begins in a nebula, which is a large cloud of gas and dust in space. Under the influence of gravity, portions of this nebula begin to collapse and condense to form a protostar.

As the protostar continues to gather mass and heat up, it eventually reaches a temperature and pressure sufficient for nuclear fusion to ignite; this marks the transition into the main sequence stage, where the star spends the majority of its lifetime fusing hydrogen into helium in its core.

As the hydrogen fuel diminishes, the star’s core contracts and heats further, causing the outer layers to expand and cool, transforming it into the red giant phase. This sequence encapsulates the expected trajectory for an average star, illustrating the fundamental stages of its development and evolution.

In the context of the other choices, while each presents plausible stellar processes, they fail to represent the complete cycle of a typical star correctly. For instance, a red supergiant leading to a supernova captures the fate of significantly larger stars, not average ones, and the option involving black holes pertains to massive