Maybe the answer is : frequency of decision making
In the statement above, the correct letter of choice in the options above is letter C, was an official. Tok-chae has been held as a prisoner due to the fact that in the farmer's communist league, he was an official. It wasn't because he owes money, an enemy or even plan to steal that makes him a prisoner.
Outflow is the answer assuming that the underlined word is influx.
The source could be wrong or biased or both.
