Question: What is the primary purpose of authentication in the context of a (U)SIM Application Toolkit feature?
Option 1: To enhance data transfer speeds between the UICC and network entities.
Option 2: To ensure only authorized parties can access and perform actions on the UICC and network-side entities.
Option 3: To simplify the process of updating (U)SIM applications for end-users.
Option 4: To facilitate anonymous communication between Sending and Receiving Entities.
Explanation: Authentication in this context is crucial for security, ensuring that both the UICC and entities on the network side are protected from unauthorized access. This aligns with the principle of securing interactions between authorized parties only, thereby preventing potential breaches or malicious activities.