The scientific study of mass media got started because of interest in
a. french philosopher alexis de tocqueville how media messages were used to inspire public support for world war i
b. knowing which forms of advertising were most effective
c. finding out how the public feels about political and social issues
d. how violent video images might inspire violent behavior

how media messages were used to inspire public support for World War I

Explanation:

Mass media refers to the communication technologies that are used to reach a large number of people, including developments such as newspapers, billboards, radio, magazines, television and the internet. Scientific study of mass media got started because of interest in how media messages were used to inspire public support for World War I. During this global conflict, propaganda produced or supported by the belligerent governments was blasted through the mass media for the first time. By appealing to patriotism and nationalism, and by demonizing the enemy, the aim of the mass media was to rally support for the war. One of the most enduring examples of propaganda of these times is the famous I want you for U.S. Army poster depicting Uncle Sam. Overall, propaganda during the war was considered highly effective, and by the 1920s, the word "media" was already in use to refer to these mass communication technologies. Cultural critics such Walter Benjamin and Christopher Caudwell, among others, published works on the role of mass media in the 1930s.

hygrometers and hair thermometers (often found as part of hygrometers/psychrometers) can be used to measure humidity. barometers are used to measure atmospheric pressure, while anemometers are used to measure wind speed. so the 2nd and 4th choices should be the correct answers.