Answer:
The fusion of a egg and a sperm produces a zygote with 46 (2n) chromosome number.
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).
They form a complex called chromatin
