Which of the Following Is an Advantage of Using the Radio

Which of the following is an advantage of using the radio as a media vehicle?

A) Combines sight, sound, and music
B) Highly personal
C) Ability to change message quickly
D) High quality graphics/reproduction
E) Many ad sizes available
According to Ad Lab 9-B, the advantages of using the radio as a media vehicle are:
(a) intimacy
(b) loyal following
(c) ability to change message quickly