Miss Li ________ as a biology teacher for fifteen years in our school, and now she is Party secretary of our city.

A．works

B．worked

C．had worked

D．has worked

关于甲状腺下动脉的描述，哪项是错误的？（）

A.是甲状颈干的分支

B.沿前斜角肌内侧缘上行

C.至环状软骨平面弯向下内

D.经颈动脉鞘前方至甲状腺侧叶下极

E.在甲状腺侧叶下极后方与喉返神经交叉