Mary is so careful that she makes ______  mistakes in her work.  [ ]

A. few      

B. many      

C. little       

D. a little

引起Coats病最终失明的主要原因是()

A．视网膜脱离

B．视网膜胆固醇结晶

C．静脉扩张

D．并发性白内障

E．以上都不对