Concept:Radio is a mass medium that reaches a vast geographic audience.
Explanation:Radio signals can be received in many homes, vehicles, and public places across a wide region.
This allows an advertisement to reach both urban and rural listeners quickly.
Neon signs and billboards are fixed at one location, so they are seen only by local passers-by.
Cinema advertising is limited to people who visit a theatre.
Among the given options, radio is the only medium that gives nationwide or regional coverage.
Therefore, radio generates a wider coverage than the other options.
Answer:A. radio