The ABR advertises a default route to the NSSA using a Type 7 LSA.

The ABR advertises a single Type 3 summary LSA to the backbone area for all Type 1 and Type 2 LSAs in the 192.168.16.0/20 range.

The ABR advertises a Type 5 external LSA to the backbone area for each Type 7 LSA in the NSSA.

The ABR does not summarize any routes within the 192.168.16.0/20 range.

The ABR advertises a single Type 5 external LSA to the backbone area for all Type 7 LSAs in the NSSA.