Question: What is the primary reason for the PCRF to return an `INVALID_SERVICE_INFORMATION` (5061) Experimental-Result-Code AVP in response to a service request from the AF, according to 3GPP policy and charging control standards?
Option 1: The requested service is not consistent with subscription information or operator-defined policy rules.
Option 2: The Flow-Description AVPs provided by the AF cannot be handled due to restrictions defined in network handling policies.
Option 3: The service information provided by the AF is invalid or insufficient for the PCRF to perform the requested action.
Option 4: There is a temporary failure in the access network, such as an SGW failure.
Explanation: The `INVALID_SERVICE_INFORMATION` (5061) code specifically indicates that the PCRF rejects new or modified service information because it is either invalid or insufficient for the server to proceed with the requested action. This highlights the importance of accurate and complete service information from the Application Function (AF) for successful policy and charging control decisions in telecom networks.