"pull" does not contain the sound /uː/ (the long "oo" sound, like in "cool" or "food").
/uː/ is the sound found in words like food, moon, and blue.
"Pull" has the sound /ʊ/ (the short "oo" sound), as in words like foot, book, and good.
So, "pull" does not contain the /uː/ sound, making it the correct answer.
