Final answer:
c. Agency representation best describes the idea that a legislator is someone whom voters hire to represent their interests, acting as an agent for the constituents.
Step-by-step explanation:
The concept of representation that suggests a legislator acts as someone whom voters hire to represent their interests is c. agency representation. This notion is akin to a contract, where constituents 'hire' their representatives to act in their best interests, somewhat similar to an agent working on behalf of a principal in the business world. In this model, the representative acts in the interest of the constituents, much like an employee would for an employer, adhering closely to the desires and needs of the people who elected them.
Other models include the delegate model, where legislators act according to their constituents' expressed wishes, and the trustee model, in which representatives use their own judgment to decide what is best for their constituents, sometimes overriding the direct preferences of their constituents if they believe it to be in their broader interest. The politico model represents a hybrid approach, balancing the principles of the delegate and trustee models based on different situations.