Question

unison.
feeling self-conscious, christopher looked down and grinned uncomfortably. he wished his mom hadnt mentioned the call to mr. w. if christopher got cut, everyone would think he was a total loser.
christopher left the classroom and found his friends jayden and adam waiting for him in the hall.
\oh, christopher, youre such a star.\ jayden kidded.
\may we please have your autograph?\ teased adam.
christopher shoved his hands in his pockets and muttered, \come on, quit it.\
\sorry, were just messing around with you,\ said jayden. \adam and i are excited for you, really. but promise to remember us when youre a celebrity.\
crazy
big
small

Explanation:

The context shows Jayden and Adam are teasing Christopher playfully about potentially becoming famous, so the word that fits the phrase "when you're a ____ celebrity" is the one that makes sense for a well-known, famous figure. "Big" describes a celebrity who is widely known, which aligns with the playful, excited tone about his potential success. "Crazy" does not fit the structure here, and "small" contradicts the positive, teasing excitement about his future fame.

Answer:

big