What is the default interval at which Cisco devices send Cisco Discovery Protocol advertisements?

A.
30 seconds

B.
60 seconds

C.
120 seconds

D.
300 seconds

Explanation:
Cisco Discovery Protocol is a Layer 2, media-independent, and network-independent protocol that networking applications use to learn about nearby, directly
connected devices. Cisco Discovery Protocol is enabled by default. Each device configured for Cisco Discovery Protocol advertises at least one address at which
the device can receive messages and sends periodic advertisements (messages) to the well-known multicast address 01:00:0C:CC:CC:CC. Devices discover each
other by listening at that address. They also listen to messages to learn when interfaces on other devices are up or go down.
Advertisements contain time-to-live information, which indicates the length of time a receiving device should hold Cisco Discovery Protocol information before
discarding it. Advertisements supported and configured in Cisco software are sent, by default, every 60 seconds.
http://www.cisco.com/en/US/docs/ios-xml/ios/cdp/configuration/15-mt/nm-cdp- discover.html