Final answer:
The assertion that public service announcements are rooted in wartime propaganda posters is true. Propaganda has historically been used to sway public opinion and garner support for war efforts, which laid the foundation for modern public service announcements.
Step-by-step explanation:
The statement that public service announcements have their roots in propaganda posters during wartime is true. Propaganda has been a powerful tool in rallying national support during times of conflict, with significant advancements during World War I and further evolution in World War II. This can be seen through the extensive use of various media channels, like radio, movies, and especially propaganda posters which were integral in shaping public opinion and encouraging people to contribute to the war effort. Governments implemented censorship and produced posters that portrayed the enemy in negative terms, appealed to patriotic emotions, and urged men and women to support the war efforts, both on the home front and on the battlefield.
The evolution of propaganda has certainly contributed to the development and techniques used in modern public service announcements. During wartime, these posters would often appeal to citizens to become 'citizen soldiers' or present the enemy as monstrous threats. This historic use of propaganda through visual media helped establish the groundwork for the public service announcements we see today, which aim to inform and influence the public on various issues.