OSPF stub areas are an important tool for the Network designer； which of the following two shouldbe considered when utilizing OSPF stub areas？ （）

• A、 OSPF stub areas increase the size of the LSDB with the addition of Type 3 and 5 LSAs
• B、 OSPF not so stubby areas are particularly useful as a simpler form of summarization
• C、 OSPF stub areas are always insulated from external changes
• D、 OSPF totally stubby cannot distinguish among ABRs for the best route to destinationsoutsidethe areas
• E、 OSPF stub areas can distinguish among ASBRs for destinations that are external to the OSPFdomain