What is route poisoning?

Select one:

a$.$ It is information received from a router that can't be sent back to the orginating router

b$.$ It describes when a router sets the metric for a downed link to infinity.

c$.$ It sends back the protocol received from a router as a poison pill, which stops the regular updates

d$.$ It prevents regular update messages from reinstating a route that has just come up$.$

Clear my choice