问题：

[单选]

You administer a network that uses two routers， R1 and R2， configured as an HSRP group to  provide redundancy for the gateway. Router R1 is the active router and has been configured as  follows：  
R1#configure terminal  
R1（config）#interface fa0/0  
R1（config-if）#ip address 10.10.0.5 255.255.255.0  
R1（config-if）#standby 1 priority 150  
R1（config-if）#standby preempt delay minimum 50  
R1（config-if）#standby 1 track interface fa0/2 15  
R1（config-if）#standby 1 ip 10.10.0.20  
Which of the following describes the effect the standby preempt delay minimum 50 command will  have on router R1？（）

A .  The HSRP priority for router R1 will increase to 200.
B .  Router R1 will become the standby router if the priority drops below 50.
C .  The HSRP priority for router R1 will decrease to 50 points when Fa0/2 goes down.  
D .  Router R1 will wait 50 seconds before attempting to preempt the active router.