In an AM signal using voice:

Correct Answer: Option B — There is a constant amplitude carrier with complex upper and lower sidebands varying in amplitude and frequency.

Standard AM (A3E) utilizes a constant amplitude carrier combined with two sidebands. The information signal modulates the carrier, causing the sidebands to vary in both amplitude and frequency relative to the carrier, which remains at a constant power level throughout the transmission process as defined by ITU radio regulations.