Final answer:
Yellow journalism contributed most notably to public support for the Spanish-American War.
Step-by-step explanation:
Yellow journalism contributed most notably to public support for the Spanish-American War. During this time, newspapers such as the New York Journal and New York World engaged in sensationalist reporting, using bold headlines, pictures, and dramatic stories to capture readers' attention. Media magnates William Randolph Hearst and Joseph Pulitzer used this style of journalism, known as yellow journalism, to agitate for war and increase circulation. Their influence played a significant role in shaping public opinion and generating support for the Spanish-American War.