The answer is C because it mentions that Major league baseball players quit in order to help with the war effort. This means that people who were unable to play baseball previously were now able to!
"This set of circumstances created an opportunity for some people to play baseball at the highest level of the game who otherwise might not have been able to" This answer is correct because the so called "circumstances", is referring to World War II. Because World War II, people who previously weren't able to play baseball were now able.
The answer D does not make sense because it refers to the people who originally played baseball who came back home AFTER the war, therefore Peter Gray was only allowed to play for a limited amount of time. Therefore D would be the best answer for number 8.
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