Question

Which of the following is the correct sequence in the life cycle of a low-mass star?

Answer 1

I think it's the correct answer is D, thought it could be C as well

Answer 2

The correct answer is A. Protostar, main sequence star, red giant, planetary nebulosa, white dwarf.

Explanation

In astronomy, a low mass star is a term used to refer to a star that has a mass below ~ 0.6 solar masses. The life cycle of these stars consists of five stages; the first is the protostar, at this stage the star is just a gravitational collapse of different elements that form molecular clouds, which is compressed by expelling energy and gradually heating its nucleus; the second stage is the main sequence of the star, in which by means of the fusion of hydrogen atoms subjected to high temperatures, helium atoms are produced; the third stage is the red giant, in it all the hydrogen has been transformed into helium, this causes the atmosphere of the star to expand until that helium is converted to carbon; the fourth stage is the planetary nebula, in which some outer layers of the star move away from its nucleus forming clouds that are diluted in space, at the same time its nucleus continues to emit heat and light due to the high temperature it has; finally, in the fifth stage that nucleus decreases its size and turns white that informs the death of the star. So, the correct answer is A.protostar, main sequence star, red giant, planetary nebula, white dwarf.