Step 1: The correct phrase is “called on,” which means to visit someone, especially for a specific purpose.
Step 2: “Called to the house of” and “called on the house of” are incorrect, as they imply that the house is the object of the call, not the people.
Step 3: “Called to” is generally used in the context of calling someone to a place, not visiting.
Thus, the correct answer is: “called on.”