A star passes through stages of instability and stability. When core hydrogen fusion begins in a pre main sequence star, the star enters a stage of <u>stability</u>.
When the body has sufficient mass, the collapsing gas and dust burn hotter which eventually reaches temperatures enough to fuse hydrogen into helium. Thus, the star turns on and becomes a main sequence star, powered by hydrogen fusion.
A pre main sequence star is a star in the stage when it has not yet reached the main sequence. Earlier it is a protostar that grows by acquiring mass from its surrounding dust and gas.
Hence, in the pre main sequence star stage, core hydrogen fusion begins and the star enters a stage of stability.
To learn more about pre main sequence star here:
brainly.com/question/14094439
#SPJ4