In the Roman Republic, senators were elected every six years.
Explanation:
The Roman Republic was ruled by the Senate, consisting of a group of senior citizens. Each year, the Senate elected two consuls to rule Rome. The Senate met to discuss how Rome was conducted and to offer suggestions to the consuls, who were the most powerful people in Rome. The Senate had a veto right. Each elected senator lasted 6 years in office.
The senators abolished the monarchy by plotting against Tarquinius and managed to centralize the power in the newly formed republic. This was achieved by the inclusion of senators who were not members of the high-class families, but who deserved seats in the senate. They received the name patres minorum gentium, and were equal in rights with the old senators.
I say B, because across continents there have been numerous fossils found with different ages. You can even look up case studies, but the answer might not be B, its just a guess.
