肾上腺脑白质营养不良的病理表现为（）

A.脑内和肾上腺中含大量长链脂肪酸

B.肾上腺皮质萎缩

C.血管周围炎性细胞浸润位于脱髓壳病灶中心

D.枕、顶、颞叶白质可见大片脱髓壳病灶

E.周围神经同时受累

Professor Li always allows his students to voice their opinions in class, ______ sometimes their opinions are not sound.

A．so that

B．in case

C．even if

D．as though