Which two statements or sets of statements are true about the application of the qos pre-classify command？（）
A、 If the classification policy is based upon the ToS byte， the qos pre-classify command is required because the ToS byte only appears in the inner IP header.
B、 The ToS byte is copied to the outer header by default. Therefore， the qos pre-classify command is not necessary.
C、 With GRE encapsulation， the qos pre-classify command is applied on the tunnel interface. This practice allows for different OoS configurations on each tunnel.
D、 With GRE encapsulation， the qos pre-classify command is applied on the physical interface. This practice allows for different OoS configurations on each interface.
E、 With IPsec encapsulation， the qos pre-classify command is applied on the physical interface. This practice allows for different OoS configurations on each interface.
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