单选题 (While) schools developing online curricula try to strike (a balance) between profits and prestige, many educators (are confusing) about their role in this (digital world).
【正确答案】 C
【答案解析】应为被动式，将confusing改成are confused。人做主语时，表语常用—ed的形式；物做主语时，表语常用-ing的形式。