The correct answer is answer A ("Debated proposed laws").
The Senate of the Roman Republic was in charge of managing state's finances, advicing magistrates and directing the consuls over military conflicts and most improtantly, interpreting law. From very early on, this institution also had a lot of weight in the civil government. Its members were selected directly by the consuls at first and later on by censors.
Senate sessions were autonomous from the magistrate, meaning they could be carried out even without their presence. In most cases they began with a speech from the magistrate who then directed the discussion towards any issue or proposed law at hand, giving word for debate to each senator in order of seniority: first the princeps senatus (leader), ex-consuls right after, then praetors, and finishing with the newest senators.
The Senate held between 300 and 500 patrician members in their charge.
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