Question

The first life on Earth, a simple, single-celled prokaryotic bacteria, appeared on life approximately how long ago? A) 4 thousand years B) 4 million years C) 4 billion years D)

Answer 1

The answer should be C: 4 billion years ago.

Answer 2

C) 4 billion years

Step-by-step explanation:

Life of the earth originated around 3.8 billion years ago. The life is supposed to be originated in deep sea vents. The available inorganic compounds in sea vents served as energy source. Hence, the first life forms were chemoheterotrophs. The first life forms were supposed to be the prokaryotes with simple cell organization.