Re: (simple?) xpath question

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
               version="1.0">

 <!-- By default, copy all nodes unchanged -->
 <xsl:template match="@* | node()">
   <xsl:copy>
     <xsl:apply-templates select="@* | node()"/>
   </xsl:copy>
 </xsl:template>

 <!-- But skip <b> elements and only process their contents -->
 <xsl:template match="b">
   <xsl:apply-templates/>
 </xsl:template>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
               version="1.0">

 <!-- By default, copy <a> and <c> elements -->
 <xsl:template match="a | c">
   <xsl:copy>
     <xsl:apply-templates select="@* | node()"/>
   </xsl:copy>
 </xsl:template>

 <!-- But skip by every other element -->
 <xsl:template match="*">
   <xsl:apply-templates/>
 </xsl:template>

All *help*!
What is the best way to query xml with xpath to get a disjoint nodelist? Specifically i want to include just the root node alongwith a descendent node. XML:
<a>
<b>
<c>
</c>
</b>
</a>
XPATH:
//c
DESIRED RESULT NODELIST:
i.e. not this:
<c>
</c>
but rather this:
<a>
<c>
</c>
</a>