One of the latest technologies used in mobile computing is:

The correct answer is C. GPRS.

GPRS, or General Packet Radio Service, is a mobile data service that facilitates mobile internet connectivity. It allows for the transmission of data packets over the GSM (Global System for Mobile Communications) network, enabling users to access the internet and use various mobile applications effectively. While PSTN (Public Switched Telephone Network) relates to traditional telephone services, multimedia refers more broadly to content types rather than a specific technology in mobile computing. Therefore, GPRS is indeed one of the latest technologies utilized in mobile computing.