Question: Which of the following messages does not include a sub-attribute of the 3GPP Vendor-Specific attribute?
Option 1: Access-Challenge
Option 2: Accounting-Request Interim-Update
Option 3: Disconnect-NAK
Option 4: CoA-Request
Explanation: According to Table 7, the sub-attributes of the 3GPP Vendor-Specific attribute are applicable to Access-Request, Access-Accept, Accounting-Request START, Accounting-Request STOP, Accounting-Request Interim-Update and Disconnect-Request messages. Access-Challenge is not mentioned in this list, making it the correct answer.