The correct answer is: A. D/A converter.
A D/A converter, or digital-to-analog converter, is a circuit that converts digital signals into analog signals. This is necessary because computers are digital devices, while the world around us is analog. For example, sound waves are analog, but when you play a song on your computer, the sound waves are converted into digital signals so that the computer can store and process them. When you listen to the song, the digital signals are converted back into analog signals so that you can hear them.
A/D converters, or analog-to-digital converters, do the opposite of D/A converters. They convert analog signals into digital signals. This is necessary for many applications, such as recording sound or measuring temperature.
Voice recognition is a technology that allows computers to understand human speech. It is used in many applications, such as voice-activated assistants, dictation software, and speech-to-text translation.
An adapter is a device that allows two devices to connect to each other. For example, an adapter can be used to connect a USB device to a computer that does not have a USB port.
None of the above options are correct.