Answer:
C. Posters
Explanation:
Posters were the most prevalent propaganda media form because they communicated with people all throughout history. Posters were put up everywhere that the people could see and read them. The posters were able to spread ideologies and inspiration. Propaganda was used to spread information in support of a cause, especially during both World Wars. The posters helped people to get together for support, boost morale and urge action.