A BGP router should use three export policies named add-communities， no-rfc1918-routes， and rejected-unwanted. Which export statement places the add-communities policy immediately before the default BGP policy？（）

A.export [add-communities no-rfc1918-routes ejected-unwanted]；
B.export [no-rfc1918-routes add-communities rejected-unwanted]；
C.export [add-communities rejected-unwanted no-rfc1918-routes]；
D.export [no-rfc1918-routes rejected-unwanted add-communities]；