What effect on public opinion did the St. Valentine’s Day massacre have?
A. People were relieved that there were no more gangs in Chicago
B. Prohibition was called to be repealed for encouraging illegal activity
C. People were eager to join organized crime to make money in bootlegging
D. Many saw it as Prohibition working as it was intended

there were abundant sources of fuel nearby

d is the correct answer

i believe it would influence their own way of understanding things. it shall be a foundation where they can draw or start an argument.   historians are also  scientists that  have their tools of analysis and expertise to unlock a variety of difficulties such as relationships of man, origin, politics, economy, and culture. based on facts and understanding on these areas, they may shade light to extract ideas and develop options to validate a hypothesis or debunk it.

the answer is b. i did this test and got it right.