I'm pretty sure It's B or C and my guess of those would be C. Good luck!
If you really think about it is Everything from what you eat how you dress and even religion.
Historians consider letters and journals written by certain historical subjects to be absolutely crucial, since they represent an unaltered and oftentimes revealing primary source.<span>primary source documents that are useful in the study of history.</span>
Answer: The Great Leap Forward
Explanation: I just got it right on the test.