When Does a Star Become a Main- Sequence Star

question 119

Multiple Choice

When does a star become a main- sequence star?

• A)the instant when hydrogen fusion first begins in the star's core
• B)when the rate of hydrogen fusion in the star's core is high enough to sustain gravitational equilibrium
• C)when the protostar assembles from its parent molecular cloud
• D)when a star becomes luminous enough to emit thermal radiation
• E)when hydrogen fusion is occurring throughout the star's interior

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Definitions:

Environmental Factor

Any element that can affect living organisms or ecosystems, including both natural and man-made conditions.

Hormonal Fluctuations

Variations in the level of hormones in the body, which can affect a wide range of bodily functions as well as mood and behavior.

Regulation Of Hunger

The complex biological and psychological processes that manage the feeling of hunger and the intake of food.

Evolutionary Basis

The principle that behaviors or traits have developed and been maintained throughout evolutionary history because they serve adaptive functions for survival or reproduction.