How long will they wait（）

A．it, like many other dogs, always tried to please its owner
B．it, unlike many other dogs, always wanted its master to please it
C．it was more intelligent than many other dogs
D．it was the most faithful dog of his friend's

A．They help and see for blind people.
B．They have only one eye.
C．They are less intelligent than German shepherds.
D．They can only help the blind walk always along the streets.