Comments and element content for serialization

Which of the following are legal serializations for the integer 12?
	<i>1<!-- x-->2</i>
	<i><!-- x-->12</i>
	<i><![CDATA[1]]>2</i>
	<i><![CDATA[12]]></i>

In looking at the sec5.1 serialization rules, it says simple values are
character data without any subelements.  But these are siblings, not
children.

Seems like a clarification is needed.
	/r$