Node XPath- Select Node ignoring only one particular child Node

Question

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     <c>A2</c>
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Here I want an xpath to pick node only if the node value is c,d,e ...(or it can be any other value) and ignore only if the node is 'z' (in place of c)

I tried following expression but it is not working

xPath: //*[local-name() = 'a']//*[local-name() = 'b']/*[not(local-name() = 'z')]
xPath: //*[local-name() = 'a']//*[local-name() = 'b']/*[not(starts-with(local-name(),'z'))]