此题看不懂,求助!

ldzs

QUESTION 86
Refer to the exhibit. From the MAC addresses shown in the command output, to which two ports is the multicast stream 225.230.57.199 being forwarded on thisswitch? (Choose two.)
Switch#show mac- address-table multicast
A. Fa6/28
B. Fa7/20
C. Gi3/7
D. Fa4/2
E. Fa4/14
F. Fa4/38
G. Fa6/28
H. Fa5/7


Correct Answer: CE
Section: (none)
Explanation
Explanation/Reference:

拽拽的流氓

自己看看组播的方面的只是去，有相应IP地址和MAC地址的对应。自己看书看的明白。
固定组播MAC是01005e+0+23bit（这23bit是组播IP后23bit）,换算过来就对了。