You are implementing OSPF as the IGP using a single OSPF area design. The router memory usage for OSPF is too high. Which two methods can lower the OSPF memory usage? (Choose two.)
A. Enable OSPF synchronization
B. Implement multi-area OSPF
C. Enable OSPF sham links to reduce the number of LSAs
D. Implement route summarization on the ABRs
E. Enable route leaking between Level 1 and Level 2 areas
