The correct answer is d. 3.5 billion years.
Prokaryotes were the first forms of life on Earth long before simple multicellular life appeared because of their ability to withstand extreme conditions. It is believed that the first living forms were bacteria combined with archaea in the microbial mat (multi-layered sheet).
B. He found similar fossils on different continents that are separated by oceans.
According to Twain man could not have ascended from lower animals (Darwin theory of evolution) because man makes cruel and horrible decisions, rather man descends from Higher animals. He proved his conclusions about man by using specific scientific method, he subjected every postulate itself to the crucial test of actual experiment and have adopted it or rejected it according to the results.
<span>Polyploid plants are usually stronger and better</span>
