A <html>
<head>
<title>index</title>
</head>
<frameset>
<frame src="page1.htm" />
<frame src="page2.htm" />
<frame src="page3.htm" />
</frameset>
</html>
B <html>
<head>
<title>index</title>
</head>
<body>
<frameset>
<frame src="page1.htm" />
<frame src="page2.htm" />
<frame src="page3.htm" />
</frameset>
</body>
</html>
C <html>
<head>
<title>index</title>
</head>
<body>
<frameset>
<frame href="page1.htm" />
<frame href="page2.htm" />
<frame href="page3.htm" />
</frameset>
</body>
</html>
D <html>
<body>
<frameset>
<frame href="page1.htm" />
<frame href="page2.htm" />
<frame href="page3.htm" />
</frameset>
</body>
</html>