var correctchoices=new Array()
correctchoices[1]='d'
correctchoices[2]='c'
correctchoices[3]='c'
correctchoices[4]='d'
correctchoices[5]='c'
correctchoices[6]='a'
correctchoices[7]='b'
correctchoices[8]='d'
correctchoices[9]='a'
correctchoices[10]='b'
correctchoices[11]='b'
correctchoices[12]='a'
correctchoices[13]='d'