Answer:
Option (b).
Explanation:
A star is a heavenly body which emits a tremendous amount of energy by the reaction of nuclear fusion.
Sun is the smallest star in the universe.
The star stars from the proto star, this is the process of birth of a star. Then it collapse due to the gravitational pull and then it tarts emit light and energy and become a star.
After the long long time, it starts to decay and become a neutron star or the black hole.
So, the correct option is (b).