B is the correct answer. They can sometimes show an extinction but not always.
I don't know exactly what you mean but the size of a group affects its defense because there is a larger group. Therefore, more people would be protecting it, adding more to its defense.
Wheres the picture for this
I looked it up and got energy not sure though
"Gravitational attraction" is initially responsible for the formation of the clumps of matter within this interstellar cloud.
<u>Answer:</u> Option C
<u>Explanation:</u>
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.
