Which three descriptions are true? (Choose three.)
A.
 The class of service is a parameter that is used for traffic classification and marking at 
Layer 2.
B.
 The IP precedence is a parameter that is used for traffic classification and marking at 
Layer 2.
C.
 The differentiated services code point is a parameter that is used for traffic classification 
and marking at Layer 2.
D.
 The class of service is a parameter that is used for traffic classification and marking at 
Layer 3.
E.
 The IP precedence is a parameter that is used for traffic classification and marking at 
Layer 3.
F.
 The differentiated services code point is a parameter that is used for traffic classification 
and marking at Layer 3.