Answer:
D.
Explanation:
The Nebula Hypothesis is the most widely accepted to explain our solar system formation. According to the theory, the Sun and planets were formed from a giant cloud (nebula means cloud in latin) which contained gas and dust.
Then, s<u>ome gravitational event help to collapse the center</u>. With this event, <u>began to form denser regions</u>, which, as result, attracted more and more matter, the region with more concentration create the Sun and surroundings of matter create planets and other components of the Solar System.
A word naming particular person, place or thing is a Noun