Which of these forms as part of the life cycles of both low-mass and high-mass stars as a result of a star-forming nebula collapsing and spinning?

When a star-forming nebula collapses under gravity, it spins faster as it contracts and forms a protostar. Protostars are an early stage in the life cycles of both low-mass and high-mass stars. Black holes, supernovae, and white dwarfs occur only in later stages and are not shared by both kinds of stars.

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