What type of modem translates coaxial cable signals into phone lines?

The correct choice is a Digital Subscriber Line (DSL) modem, which is specifically designed to work over traditional telephone lines, not coaxial cables. DSL technology utilizes the existing telephone infrastructure to provide internet access, allowing both data and voice services to function simultaneously over the same line.

A cable modem, on the other hand, is responsible for translating signals from a cable television service (typically using coaxial cable) into internet data, which is distinct from how DSL operates. Power injectors are used in networking to provide power to devices like access points and do not serve to translate signals. An Optical Network Terminal (ONT) is employed in fiber-optic networks to convert optical signals into electrical signals but also does not handle coaxial signals or functions primarily related to standard telephone lines.

Understanding this distinction is essential for identifying the appropriate type of modem based on the type of connection being used. In this case, the question specifically asks about translating coaxial signals into phone lines, which aligns with the function associated with a DSL modem in the context of using phone lines for internet access.