Which class is always present even though it is not in the configuration snip?

Refer to the exhibit. Which class is always present even though it is not in the configuration snip?

A.
class best-effort

B.
class class-default

C.
default class

D.
best-effort class

E.
class class-scavenger

Explanation:
The class-default is in every policy-map by default and it cannot be removed. The
class-default class is used to classify traffic that does not fall into one of the defined classes. Once

a packet is classified, all of the standard mechanisms that can be used to differentiate service
among the classes apply. The class-default class was predefined when you created the policy
map, but you must configure it. If no default class is configured, then by default the traffic that does
not match any of the configured classes is flow classified and given best-effort treatment.
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