Which statement is true about route summarization for routes announced to the backbone by Area 1?

Exhibit:

Which statement is true about route summarization for routes announced to the backbone by Area
1?

A.
By default, routes will not be summarized.

B.
By default, routes will be summarized on the network boundaries.

C.
By default, routes will be summarized to Area 3 (NSSA) but not to Area 2.

D.
By default, routes will be summarized based upon the summarization schedule configured in
the CE-router.

Explanation:
Summarizing is the consolidation of multiple routes into one single advertisement. This is normally
done at the boundaries of Area Border Routers (ABRs). Although summarization could be
configured between any two areas, it is better to summarize in the direction of the backbone. This
way the backbone receives all the
aggregate addresses and in turn will injects them, already summarized, into other areas. There
are two types of summarization:
1. Inter-area route summarization
1. External route summarization

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