The German is the only one without a pet,
therefore he must be the one who owns the fish.
There are 5 houses in five different colors. In each house lives
a person with a different nationality. These five owners drink a certain
drink, smoke a certain brand of cigar, and keep a certain pet. No owners have
the same pet, smoke the same brand of cigar or drink the same drink. The
question is --- who owns the fish?