考博考试

【单选题】From Paragraph 5 the author emphasizes ______.
A．the danger of viruses
B．the common existence of virus particles
C．the short life span of viruses
D．the difficulty in killing viruses
网考网参考答案：B
网考网解析：
[解析] 根据“Viruses are Slightlly different．You need only pick up a few virus particles to infect your self with a cold or flu，and virus particles can survive on surfaces for days．so disinfecting the surfaces in the home should，in theory，reduce the chances of picking up a bug．”可知，B项为正确答案。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>