The question is: Who owns the fish?
Clues:
The Brit lives in the red house.
The Swede keeps dogs as pets.
The Dane drinks tea.
The green house is on the left of the white house.
The resident of the green house drinks coffee.
The person who smokes Pall Mall rears birds.
The resident of the yellow house smokes Dunhill.
The resident of the centre house drinks milk.
The Norwegian lives in the first house.
The person who smokes Blends lives next to the one who keeps cats.
The person who keeps the horse lives next to the one who smokes Dunhill.
The person who smokes Bluemasters drinks beer.
The German smokes Prince.
The Norwegian lives next to the blue house.
The person who smokes Blends has a neighbour who drinks water.