Can someone clean up this function for me?

This function seems inefficient.

I want it to just return the clients(user) mac address with as little code as possible.

Imports System.Management

Private Function GetMacAddress() As String

        Dim mc As System.Management.ManagementClass = New ManagementClass("Win32_NetworkAdapterConfiguration")
        Dim moc As ManagementObjectCollection = mc.GetInstances()
        Dim mo As ManagementObject

        Dim strMacAddress As String = "N/A"
        For Each mo In moc
            If mo.Item("IPEnabled") Then
                strMacAddress = mo.Item("MacAddress").ToString()
            End If
        Next

        If IsNothing(strMacAddress) Then
            Return "n/a"
        Else
            Return strMacAddress
        End If

    End Function