How do I add multiple Namespace declarations to an XDocument?

Question

I\'m using an XDocument to build an Xml document in a known structure. The structure I am trying to build is as follows:

Answer 1

Do you mean:

new XAttribute(XNamespace.Xmlns + "ns4", ns4),
new XAttribute(XNamespace.Xmlns + "ns3", ns3),
new XAttribute(XNamespace.Xmlns + "ns2", ns2),