The root element in XML data has the xmlns:prod$="$http:$//$www$.$cisco.com$/$ns$/"$ namespace. How can you easily apply the namespace to all elements with the least amount of effort?

Nothing. The namespace will be applied to all child elements by default.

Using the and syntaxes, only apply the namespace to the child elements. Subchild elements inherit it automatically.

Using the and syntaxes, apply the namespace to the child and subchild elements.

Change the namespace type to default.