Answer:
A. A bicameral legislature with both chambers popularly elected
Explanation:
In Popular election, the people could directly choose the representative they want without having to rely on the party.
and
Bicameral legislature allow the law-making process to be handled by two houses within the government. These houses tend to oppose one another. Even though it's sound inefficient, having this type of opposition actually minimize the power of the central government. Each houses will prevent the opposition from becoming too tyrannical.
The combination of the two will be the best option to represent large , populous state which most likely consist of different groups of people with differing opinion.