单项选择题

A.$("#AddFile").click(function () {var id = "File" + ++lastId; var item =$(".File:first").clone(true); $("input:file", item).attr({ id: id, name: id }); item.insertBefore("#AddFile"); });
B.$("#AddFile").click(function () {var id = "File" + ++lastId;$(".File:first").clone(true).attr({ id: id, name: id }).insertBefore("#AddFile"); });
C.$("#AddFile").click(function () {var id = "File" + ++lastId; });
D.$("#AddFile").click(function () {var id = "File" + ++lastId;var item = $(".File:first").clone(true); $("input:file", item).attr({ id: id, name: id }); item.insertAfter("input[type=file]"); });