The correct answer is D) What life was like for a crusader making the journey to Jerusalem.
This source, "Deeds of the Franks," would be most valuable for a historian who wants to know more about what life was like for a crusader making the journey to Jerusalem.
The Historian has to collect many valid sources to do its research. Primary sources such as photographs, letters, documents from that epoch, or secondary resources like books from other authors and encyclopedias. The source referred is a book called "The Deeds of the Franks and Other Jerusalem-Bound Pilgrims: the Earliest Chronicle of the First Crusades, " written by Nirmal Dass, that tells many stories about the First Crusade.