Identify the functions below as belonging to one of these radio transmission devices: oscillator, transmitting antenna, microphone, or modulator. A. Sends out radio waves having the same frequency as the current supplied by the oscillator. B. Enables the waves produced by the antenna to “carry” the pattern of the sound waves picked up by the microphone. C. Converts a direct current into a high-frequency alternating current. D. Picks up sound waves and converts them into suitable electric current with the same pattern as the sound waves.