模拟选择题多选

<!--<br><br>Code highlighting produced by Actipro CodeHighlighter (freeware)<br>http://www.CodeHighlighter.com/<br><br>-->  1 
 2 
 3  < script  language =javascript >
 4  function  changeselect(selectname)
 5  {
 6  answer.innerText = ""
 7  for (i = 0 ;i <= yesanswer.length - 1 ;i ++ )
 8  {
 9       if (yesanswer[i].checked)
10      answer.innerText = answer.innerText + yesanswer[i].value
11  }
12  }
13  </ script >
14  鞋垫具有哪些功能　（ < span  id =answer ></ span > ） < br >
15  < input  name ="yesanswer"  type ="checkbox"  value ="A"  onClick ="changeselect(this)" >
16                                  A.消除脚气脚臭、风湿光节炎痛 < br >
17  < input  name ="yesanswer"  type ="checkbox"  value ="B"  onClick ="changeselect(this)" >
18                                  B.促进循环          < br >
19  < input  name ="yesanswer"  type ="checkbox"  value ="C"  onClick ="changeselect(this)" >
20                                  C.A，B答案均是                                               < br >
21  < input  name ="yesanswer"  type ="checkbox"  value ="D"  onClick ="changeselect(this)" >
22                                  D.能强筋健力
23