An engineer is adding user accounts to Cisco Unity Connection and needs to limit the maximum length of messages. Which aspect defines this limit when adding new accounts?

User templates define default field values used when creating new accounts in bulk, but they do not enforce runtime message length limits.

Partitions and search spaces control call routing and dialing scope, not message storage or length policies.

The Class of Service (CoS) in Cisco Unity Connection is the administrative object that enforces message storage and playback constraints, including the maximum length of recorded voice messages. When creating or editing user accounts, assigning a CoS directly determines the message length ceiling that applies to that user.

The mailbox store determines which physical storage location holds a user's messages but does not configure maximum message duration.

User roles define administrative privileges within the Unity Connection web interface and have no effect on voicemail message length.