Which is a design concept used to stop routing loops with distancevector dynamic routing protocols?

A. Use of a topology database
B. Use of holddown timers
C. Use of anti-flapping ACLs
D. Use of counting-to-infinity conditions

B. The use of holddown timers allows the convergence of the network routing tables. This is used to hold down changes to the routing table before convergence can happen and a routing decision is hastily made by RIP.