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Why do audio signals need a carrier wave for radio transmission?
AThey are absorbed by the air
BAntennas would be too large
CThey carry too little energy
DTheir wavelength is too short
Answer & Solution
Correct answer: B. Antennas would be too large
Audio frequencies have wavelengths of kilometres, so a quarter-wave antenna would be huge; a high-frequency carrier allows a small antenna.
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