What is the significance of Candy and his dog?

a
Candy's dog being put down foreshadows Candy's future as he gets older and less useful around the ranch
b
Candy's dog shows the need for companionship around the ranch
c
Candy and his dog represent the American Dream
d
Candy and his dog represent the norms of American society

a. Candy's dog being put down foreshadows Candy's future as he gets older and less useful around the ranch.