Answer:
Gravity is a force that combines all the particles of "interstellar cloud" together to form a star.
Step-by-step explanation:
A star is a "luminous ball of gas" made from the gases of helium and hydrogen and it is held under the action of gravity. Sun is the nearest star present to the earth and the nuclear fusion process is proposed to develop various stars in the galaxy.
Interstellar cloud indicates the combination of various gas, plasma, dust in the galaxy. This cloud contains 16 hydrogen atoms for every helium atom and also contains traces of carbon, iron and nitrogen atoms.
Gravitational force compresses the interstellar cloud and triggers them to result in a star.