What is an appropriate situation for configuring an interface as a silent TRILL access port?

A.
The interface connects to a downstream non-TRILL switch, which is connected to
another TRILL switch. The administrator does not want the interface to carry encapsulated
TRILL traffic.
B.
The interface connects to a downstream non-TRILL switch, which is connected to
another TRILL switch The administrator wants the interface to provide a backup path for
encapsulated TRILL traffic
C.
The interface connects directly to server NICs. and it is a bridge aggregation on an IRF
virtual device.
D.
The interface connects to another TRILL switch, which has a higher DRB priority than
this switch
answer C
any one can confirm?
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A.
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CORECT IS C
trill link-type access alone (silent mode)
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C
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C
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