Amajor event in the french revolution happened on july 14, 1789, when a mob stormed the bastille, a notorious prison in paris. how can historians today use primary sources to determine that this date is accurate? a. read french letters from the 1700s and search for references to the event's date. b. ask french citizens who directly experienced the event to confirm the date. c. examine a european history book popular in modern-day france.