问题
单项选择题
We were shocked by the extent to ______ teachers' decisions served the interests of the school rather than those of the students.
A．which
B．that
C．why
D．what
答案
参考答案：A
解析： 本题测试从句中的连接词。在四个选项中只有which前可以加介词，其他选项均不可以。短语“to the extent”意为“到……程度”。