I got a question for you: On Christmas morning, 1909, in a quaint Midwestern town, Jim Dear gives his wife Darling an American cocker spaniel puppy that she names Lady. Lady enjoys a happy life with the couple and befriends two local neighborhood dogs, Jock, a Scottish terrier, and Trusty, a bloodhound. Meanwhile, across town, a stray mongrel called the Tramp lives on his own, dining on scraps from Tony's Italian restaurant and protecting his fellow strays Peg (a Pekingese) and Bull (a bulldog) from the local dogcatcher. One day, Lady is saddened after her owners begin treating her rather coldly. Jock and Trusty visit her and determine that their change in behavior is due to Darling expecting a baby. While Jock and Trusty try to explain what a baby is, Tramp interrupts the conversation and offers his own thoughts on the matter, making Jock and Trusty take an immediate dislike to the stray and order him out of the yard. As Tramp leaves, he reminds Lady that "when the baby moves in, the dog moves out."

Based on this passage, what kind of dog is jock on lady and the tramp?
Let's think first:
The relevant sentence in the passage is: Lady enjoys a happy life with the couple and befriends two local neighborhood dogs, Jock, a Scottish terrier, and Trusty, a bloodhound.
Therefore, the answer is a Scottish terrier.