This clouds are commonly called as a solar nebula. This is
where some of the planets, like our planet Earth are formed. This clouds, are
made of intergalactic space that is filled with clouds of gas (Helium and
Hydrogen) and dust which to be known as molecular clouds.
Answer:
The answer is:
D. The population must be very large.
Hope that helps :)
Pre-Cambrian Era. Earth formed and became a planet 600-3,300 million years ago.
Paleozoic Era. Ancient life. Volcanoes and mount formed.
Mesozoic Era. Middle life (Industrial Ages, Evolution of human technology)
Cenozoic Era. Present life