A study of a specific population as it changes over a period of time is known as (A) Demographic analysis (B) Population analysis (C) Cohort analysis (D) Cluster analysis Correct Ans: (C) Explanation: Cohort analysis studies a specific population as it changes over time. Researchers track a group of individuals who share common characteristics, such as birth year, education, or media consumption habits. This method helps analyze long-term trends in behavior, preferences, and societal shifts. In mass communication, cohort analysis plays a crucial role in understanding audience behavior. For example, researchers may examine how people born in the 1990s have adapted to digital media compared to older generations. By observing their changing media habits over years, marketers and media planners can design strategies that align with their evolving preferences. Cohort analysis also helps advertisers target specific age groups. A study on Generation Z’s social media habits may reveal how their content consumption differs from Millennials. These insights allow brands to develop personalized campaigns, ensuring higher engagement. Moreover, news organizations use cohort analysis to study how different age groups respond to political events or media coverage. This helps shape content strategies for newspapers, television, and digital platforms. However, cohort analysis requires long-term data collection, which can be time-consuming. Researchers must ensure that external factors, such as economic changes or technological advancements, do not distort findings. Despite these challenges, it remains a valuable tool for studying audience evolution. In conclusion, cohort analysis helps researchers track population changes over time. It provides insights into audience behavior, media consumption, and marketing trends. Understanding these patterns allows businesses and media organizations to adapt effectively to shifting consumer needs.