What is the main function of digital and video cameras?

The primary function of digital and video cameras is to capture images and videos. These devices are specifically designed to record visual information, whether in still photographs (images) or moving sequences (video). They utilize a sensor to convert light into electrical signals, which are then processed to create digital files that can be stored, edited, and shared.

While other devices might play music, display television programs, or store data, these functionalities do not encapsulate what digital and video cameras are built for. Their core purpose revolves around image and video capture, making option B the most accurate choice in this context.