<span>it's D: All astronauts had master’s or doctorate degrees, but only two were jet pilots; consequently, the astronauts with no flight experience had to complete one year of flight training.
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The public could be given less credible information, for it was given with an extra unnecessary emphasis. The caster could make the story seem more/less or a problem.
The theme is a more specific topic....theme is the main messaged passed on through writing while a topic is the major subject explained in writing.