[no] cdp run is a global command. The valid config-if command is no cdp enable.

Answer as below configuration:
on R1
config terminal
ipv6 unicast-routing
inter eth0/1
ip addre 192.168.1.1 255.255.255.240
ipv6 addre 2001:db8:aaaa::1/64
not shut
end
copy running start
on R2
config terminal
ipv6 unicast-routing
inter eth0/1
ip address 192.168.1.14 255.255.255.240
ipv6 address 2001:db8:aaaa::2/64
not shut
end
copy running start
---------------------
for test from R1
ping ipv6 2001:db8:aaaa::1
for test from R2
ping ipv6 2001:db8:aaaa::2

link flapping. The answer follows directly from normal Cisco device behavior and the wording of the scenario. Cisco CCNA 200-301 v1.1 includes this under Network Access, where the exam expects engineers to recognize the device behavior that actually produces the required outcome. The question is best solved by reading the operational clue rather than choosing a familiar acronym. The other choices are either adjacent technologies, wrong-layer functions, or settings that would not produce the stated result. In a production network, the wrong choice would normally create an outage, leave a management or security gap, or send troubleshooting toward the wrong subsystem. The selected answer is the one that matches the control-plane, data-plane, wireless, security, services, or automation mechanism described in the question. That is why it remains the verified answer for this item.