I'd say it's definitely D
The assassination of President John F. Kennedy on November 22, 1963, took place in a radically different era. The adoption of radio in the 1920s and television in the 1950s created a nationwide audience for news. Word of the shooting in Dallas spread within minutes over both broadcast media. People not only heard about the tragedy in their homes or workplaces, but the development of affordable portable radio receivers meant that people in cars or in other outdoor areas could also listen to the latest bulletins. The broadcast audiences then verbally spread the news to other people directly or via telephone.
The sentence that would best fit at the beginning of a first paragraph and would also make the best topic sentence is: Mammoth hot springs is a popular attraction because the springs are unique. The correct answer would be option D. This sentence is the correct answer because it is the only sentence that introduces the topic.
Answer:
the Greeks' emphasis on the individuals is one major cornerstone of western civilization." A social theory favoring freedom of action for individuals over collective or state control. "Indeed, the spirit of individualism as defined by the Greeks is still alive and well in modern American culture and society."
hope this helps in any way