What are two characteristics of an OSPF link-state update? (Choose two.)

A.
A link-state update can be sent directly after an adjacency is formed.

B.
A link-state update can only contain a single link-state advertisement (LSA).

C.
A link-state update is sent in response to a link-state request.

D.
A link-state update is used to determine which router is in charge of the database exchange.