—What's your father?

—He's a teacher. He          math at a school.   [ ]

A. teaches

B. taught

C. will teach

D. has taught

女性，50岁，有糖尿病，低热、咳嗽3周。胸片示右下叶背段3cm大小空洞，内壁光整，周围有斑点状阴影。最可能的诊断为：（）

A.肺不张

B.肺癌

C.金黄色葡萄球菌肺炎

D.继发型肺结核

E.肺囊肿