Which configuration allows the virtual IP address to respond to pings?

A.
[edit interfaces fe-0/0/0 unit 50 family inet address 192.168.0.12/24] user@RouterA# show
vrrp-group 50 {
virtual-address 192.168.0.1;
fast-interval 250;
preempt;
accept-data;
}

B.
[edit interfaces fe-0/0/0 unit 50 family inet address 192.168.0.12/24] user@RouterA# show
vrrp-group 50 {
virtual-address 192.168.0.1;
fast-interval 250;
no-preempt;
no-accept-data;
}

C.
[edit interfaces fe-0/0/0 unit 50 family inet address 192.168.0.12/24] user@RouterA# show
vrrp-group 50 {
virtual-address 192.168.0.1;
fast-interval 250;
accept-icmp;
}

D.
[edit interfaces fe-0/0/0 unit 50 family inet address 192.168.0.12/24] user@RouterA# show
vrrp-group 50 {
virtual-address 192.168.0.1;
priority 220;
advertise-interval 10;
preempt;
accept-packets;
}

Explanation:
Impact of disabling VRRP preemption :

> If you increase the priority of the Backup router, when the Master router is present, the VRRP backup router will NOT become the master router.

> If the VRRP preemption is disabled on VRRP Master router, and if the VRRP Master is rebooted, the VRRP backup router becomes VRRP Master router. When the old VRRP Master router comes back, it will NOT become VRRP Master (even though it has higher priority as compared to the new VRRP Master Router) and will remain VRRP backup router.

Configuring VRRP Preemption

ip vrrp preempt

* Use to enable preemption.
* When preemption is enabled, a backup router always takes over the responsibility of the master router. When preemption is disabled, the lower- priority backup is left in the master state.

Example

host1(config-if)#ip vrrp 10 preempt

* The default is enabled.
* Use the no version to disable preemption.

By default, a higher-priority VRRP backup switch preempts a lower-priority master switch. To explicitly enable this behavior, include the following statement:
preempt;
To prohibit a higher-priority VRRP backup switch from preempting a lower-priority master switch, include the following statement on the lower-priority switch:
no-preempt;

You can include these statements at the following hierarchy level:
* [edit interfaces interface-name unit logical-unit-number family inet address address vrrp-group group-id]

Description

Enables the backup router to process packets with an IP destination address equivalent to the virtual addresses while the backup router is in the master state. The router ignores this attribute when the VRRP entry uses a priority of 255. You must use the default state (disabled) to comply with RFC 3768. When disabled, the master router drops any packets with an IP destination address equivalent to the virtual address. The no version restores the default value, disabled.

Note: When using this attribute and also restricting incoming packets to ICMP only, you must use policy filters to accept only ICMP packets with the virtual address as the destination address.

Options
vridVRID identifier; a number in the range 1255