如果污染物造成孔堵塞超过50%,就要清洁显示组件后面的孔。
A.If as many as 50% of the holes are contaminated, you should clean the display units behinds the holes. B.The holes on the bottom of the display unit should be cleaned once over 50% of them are clogged due to contamination. C.If contamination causes a blockage of more than 50 percent of the holes, then clean the holes on the rear of the display units.正确答案C
