Final answer:
The agenda-setting theory is the concept that the media controls the spotlight on various topics, influencing public perception of important issues.
Step-by-step explanation:
The theory that assumes the media spotlight some issues, events, and people while downplaying others is the agenda-setting theory. This theory suggests that the media has the power to determine which topics are given prime attention and thus guide what the public thinks about. According to the agenda-setting theory, the media decides which issues deserve public attention by putting a spotlight on certain subjects, which subsequently influences the public's perception of what is important. By highlighting certain issues, the media can shape the public's perception and awareness of those issues.