9. Only under special circumstances to take make-up tests.
A
are freshmen permitted
B
freshmen are permitted
C
permitted are freshmen
D
are permitted freshmen
句意为：只有在特殊情况下，新生才会被允许补考。否定词谓语句首，句子谓语半倒装。系动词提到主语前面。所以选择A。
此题是倒装句，首先要明确句意，其次判断句型。
用法规则。