The book Mourt's Relation: A Journal of the Pilgrims at Plymouth most likely contains

A.firsthand accounts of the Pilgrims' landing at Plymouth.

B.a historical account of the Pilgrims' voyage to New England.

C.firsthand accounts of why the Pilgrims left Europe.

D.a historical account of the Pilgrims' interactions with American Indians.

Option A. The book "Mourt's Relation: A Journal of the Pilgrims at Plymouth" most likely contains firsthand accounts of the Pilgrim's landing at Plymouth.

Explanation:

The book is most likely a firsthand recollection of the Pilgrims' landing at Plymouth due to two different facts that can be found in the book's title: the word "journal" and the words "Pilgrims" and "Plymouth".

The word "journal" is giving the readers the idea that the book will be presented in the form of firsthand recollections of the travellers that, in this case, went from Europe all the way to America. A journal refers to a daily record of activities.

Then there are the words "Pilgrims" and "Plymouth" which gives the reader the idea that these journal entries are going to be related to the Pilgrims landing at Plymouth, and their experiences there.