NBAR is deployed on the network as part of network optimization. Which technology is critical to recognize new applications on the network?

A.
PDLM

B.
ACLs

C.
code upgrade

D.
additional licenses

Explanation:
also known as” Packet Description Language Modules”
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/qos_nbar/configuration/15-mt/qos-nbar-15-mt-book/nbarapp- recog-mods.html
Adding application recognition modules (also known as Packet Description Language Modules [PDLMs]) is an optional process. However, adding PDLMs extends
the functionality of Network-Based Application Recognition (NBAR) by enabling NBAR to recognize additional protocols on your network.