The oldest organisms and are divided into two groups, the acheabacteria and the eubacteria. a) algae b) eukaryotes c) prokaryotes d) viruses

The correct answer is -

C)Prokaryotes.

Explanation:

Prokaryotes are the group of organisms that do not possess true nucleus and membrane bound subcellular organelles (unlike eukaryotes) such as bacteria.

These organisms are divided into two domains (according to three domain system of classification) that are acheabacteria (such as Methanogens) and the eubacteria (such as E.coli). They are the oldest group of organisms.

Thus, option C) is the right answer.

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