与胆固醇沉积有关的角膜病变( )

A．角膜颗粒状营养不良

B．角膜斑块状营养不良

C．角膜格子状营养不良

D．中央结晶状角膜营养不良

E．Fuchs角膜营养不良

It is uncertain _____ side effect the medicine will bring about, although about two thousand patients have

taken it.[ ]

A. that

B. what

C. how

D. whether