Final answer:
The relation (complete mailing address, house) is a function, but the relation (house, complete mailing address) is not. Option D.
Step-by-step explanation:
The correct statement describing the sets is D) The relation (complete mailing address, house) is a function, but the relation (house, complete mailing address) is not.
A function is a relation where each input has exactly one output. In the relation (complete mailing address, house), each complete mailing address corresponds to one house, so it is a function.
However, in the relation (house, complete mailing address), there can be multiple houses that correspond to the same complete mailing address, so it is not a function.
So Option D.