083C B
 In an AM signal using voice:
a) Varying the amplitude of the carrier and employing both sidebands without the carrier.
b) There is a constant amplitude carrier with complex upper and lower sidebands varying in amplitude and frequency.
c) Varying only the amplitude of the carrier, depending on Double or Single-Sideband operations.
d) Varying the amplitude of the carrier and employing both sidebands and the carrier.
