The core of a network has four routers connected in a square design with Gigabit Ethernet links using /30 subnets. The network is used to carry voice traffic and other applications. Convergence time is taking more than expected. Which three actions would you take to improve OSPF convergence time？（）

• A、Increase MTU of the interfaces to accommodate larger OSPF packets.
• B、Change the network type to point-to-point on those links.
• C、Reduce SPF initial timer.
• D、Increase hello interval to avoid adjacency flapping.
• E、Enable OSPF