Which of the following breed of dogs is the smallest?

Explanation

Great Dane is the largest dog breed. The breed was previously bred in Denmark and Germany. In Germany it goes by the name "Deutsche Dogge" (German dog) and in Denmark it's called "Grand Danois" (Great Dane). In 1937 it was decided that the breed's official country of origin should be Germany. However, it is widely believed that the dog actually originated from Iraq. Chihuahua is the smallest breed of dog. It originates from the state of the same name in Mexico.