According to the nebular theory, a solar system begins when an interstellar cloud, containing approximately 75% hydrogen, 25% helium and traces of other elements, begins to form areas of higher concentration, or clumps. What is initially responsible for the formation of the clumps of matter within this interstellar cloud?
A) kinetic energy
B) different densities
C) gravitational attraction
D) extremely high temperatures

"Gravitational attraction" is initially responsible for the formation of the clumps of matter within this interstellar cloud.

Option C

Explanation:

About 4.6 billion years ago, the solar systems were a bunch of gases and dusts, referred to solar nebula. Gravity squeezed the material as it started to rotate, creating the sun at the middle of the fog.

The rest of the material began to accumulate with the sunrise. The smaller particles moved together to form larger particles that were connected by gravity. As lumps develop, gravity increases and turns into kinetic energy of moving particles that collide and produce heat.

i'd say that the moon rock is about 2.2 billion years old.

b. the carbon cycle ensures living things have a source of hydrogen