In an IS-IS environment, what happens when the designated IS router crashes?

A.
The elected backup designated router takes the place of the DIS indefinitely without the
necessity of a new election.

B.
A new election process occurs immediately, establishing a new DIS until a router with a higher
priority or MAC address establishes an adjacency.

C.
The elected backup designated router takes the place of the DIS temporarily without the
necessity of a new election, until the original DIS comes back online.

D.
A new election process occurs immediately, establishing a new DIS that will remain in place
indefinitely.