When asked about HD Radio, what does Technician A correctly say HD stands for?

The term "HD" in HD Radio actually stands for "High Definition radio." This technology allows for improved audio quality and more accurate transmission, utilizing digital encoding methods to offer a clear signal and additional features such as artist information and song titles.

While "Hybrid Digital" may refer to a characteristic of the technology, where analog and digital signals coexist, it is not the formal definition of what HD stands for. High Fidelity radio generally refers to audio reproduction that is very faithful to the original recording, but it does not pertain specifically to HD Radio. Therefore, the correct answer is that HD stands for High Definition radio, affirming that this technology aims to enhance both the audio experience and the overall functionality of radio broadcasting.