Which is not an effective organizing principle for the study of history?
a. eras
b. major time periods
c. topics
d. wars
e. year-by-year accounts

d

Explanation:

long periods of time occur in between and important events may happen during these times

E. year-by-year accounts, as it would become too much information that would take up too much time if you studied every year of history in detail.

(hope this helps!)

american troops were forced to withdraw following deadly bombings.

explanation:

the answer is false.