A.document.myform.selCity.options.clear() B.document.myform.selCity.options.deleteAll() C.document.myform.selCity.options.length=0 D.document.myform.selCity.options.size=0
A.background B.backgroungImage C.image
A.〈HTML〉 B.〈HEAD〉 C.〈BODY〉 D.〈TITLE〉