What are the two reasons for the appearance of 0.0.0.0 as the next hop for a network in the show ip bgp command output？（）
- AThe network was originated via redistribution of an interior gateway protocol into BGP
- BThe network was defined by a static route
- CThe network was originated via a network or aggregate command
- DThe network was learned via EBGP
- EThe network was learned via IBGP