Stage 4 sleep lasts______.

A．feels happy, thinking of how nice his friends were to him
B．feels he may not have "read" his friends' true feelings correctly
C．thinks it was a mistake to view Jim as a friend
D．is sorry that his friends let him down

A．is just being friendly
B．expresses the same meaning as "You're a lucky guy." or “You’re a lucky gal."
C．is humorous to apply the word "dog" to people
D．has a hidden jealous feeling behind the words