Answer:B.
It was used to prove that smoking causes health problems.
Explanation:
The answer is; D
The simplicity of the prokaryote bacteria cells can depict the origin of life. It is simply composed of microscopic unit enclosed in a plasma membrane and cell wall. The inside contains a small DNA molecule, ribosomes and cytoplasm (they have no organelles). They have been around for 2 billion years on earth before other organisms evolved from them.
A population of organisms must exist. There must be variation among the members of the population. There must be a mechanism by which some members of the population can produce more offspring than other members. There must be a mechanism by which the variation among members of the population is passed on to their offspring.
