Most stars are at what point in their life cycles? a. supergiant c. main sequence b. giant d. white dwarf

c. main sequence

The nuclear fusion reaction is the natural process which occurs in the stars which is responsible for their development. The size of the star changes at different stages of their life. A cloud, dust and gas combine to form nebula which is the initial stage of star formation. The star undergoes multiple nuclear fusion reactions with the surrounding heavy compounds like helium, carbon dioxide and hydrogen to attain a stable form. The main sequence is the stable form of star and it takes million's of years to attain this form. Most of the stars in the galaxy are in the main sequence.

answer; the tunica intima also called tunica interna, consists of elastic fibers,connective tissue and smooth muscle cells;