Correct option is A
SIM stands for Subscribers Identity Module. It is a small card used in mobile phones and other devices to store information about the subscriber's identity. The SIM card holds data such as the user's phone number, network authorization, and personal security keys, enabling users to access mobile networks and make calls or send texts. SIM cards are essential for GSM (Global System for Mobile Communications) networks. They also allow users to transfer their subscriber identity across devices by simply switching the SIM card from one phone to another. The SIM card technology has undergone significant evolution, with modern eSIM (embedded SIM) technology offering greater flexibility and security.
