Which of the following is not a function of a modem?

The correct answer effectively identifies a function that is typically not associated with a modem's primary capabilities. A modem primarily focuses on modulating and demodulating signals, which involves converting digital data from a computer into analog signals for transmission over telephone lines or cable systems, and vice versa. Additionally, it converts signals for data use and can sometimes amplify signals to ensure data integrity over distance.

While some modem devices may enable wireless connectivity, this is not inherent to the primary function of a modem itself. Wireless connectivity is often more closely associated with routers, which can provide wireless networking capabilities by distributing the internet connection within a localized area. Therefore, identifying wireless connectivity as not being a direct function of a modem correctly distinguishes the unique role that each device plays in a network setup.