From a design perspective which two of the following OSPF statements are most relevant? (Choose two)

A.
OSPF stub areas can be thought of as a simple form of summarization

B.
OSPF cannot filter intra-area routes

C.
An ABR can only exist in two areas – the backbone and one adjacent area

D.
Performance issues in the Backbone area can be offset by allowing some traffic to transit a non-backbone area

E.
The size of an area (the LSDB) will be constrained by the size of the IP MTU