Review the passage:
Joey idolizes his older brother David. Combing
his hair in the style that David wears, drinking coffee black with five
sugars, and giving teachers the same lame excuses for late homework. As
a consequence, everyone calls Joey "David" by mistake!
You chose the first part, Joey idolizes his older brother David. This part has a main clause: Joey is the subject; idolizes is the verb. A fragment will not have a main clause.