食管上皮属于（）。
A、单层柱状上皮
B、复层扁平上皮
C、假复层柱状纤毛上皮
D、内皮
E、变移上皮
参考答案：B
When changing lanes, a driver should use his turning signal to let other drivers know ___.
A．whichever lane he is entering
B．which lane he is entering
C．whichever lane is he entering
D．which lane is he entering
深反射
