If left alone outside, dogs and cats can be very smart in their search for warm shelter. They can dig into snow banks or hide somewhere. Watch them closely when they are left outdoors, and provide them with shelter of good quality. Keep an eye on your pet's water. Sometimes owners don't realize that a water bowl has frozen and their pet can't get anything to drink. Animals that don't have clean and unfrozen water may drink dirty water outside, which may contain something unhealthy for them....
If pets are left on their own outdoors in cold weather, they may ________.

A．run short of clean water

B．dig deep holes for fun

C．dirty the snow nearby

D．get lost in the wild