The purpose of a bibliographic card in the index-card method of note-taking is to record
a) quotations, paraphrases, and summaries
b) mla-style source information
c) autobiographical information about the author of the source
d) the vocabulary associated with academic research

The correct answer is The purpose of a bibliographic card in the index-card method of note-taking is to record (b.) MLA-style source information.

A bibliographic card is a card in which the author who has written a work used as a source for information for a research is given credit. When writing a bibliographic card it is necessary to include the following information: author of the source, 2) title of the source, 3) city of publication, 4) publisher, 5) year of publication. For instance, the bibliography card in the index card for William Burns' book A Brief History of Great Britain should be:  

Burns, William. A Brief History of Great Britain. New York, Facts on File, 2010.

Context lets people know what the circumstances of the characters are, and what influences that they may have, and such other things like that.

For example in the story 'Owl Creek Bridge' that was written by Ambrose, It started with the description of Peyton Farquhar being tied with his wrist bounded with a cord and a rope encircling his neck, this narrated that he either was captured or was being sentenced to death for a serious crime.

As his death came closer thoughts of escaping flooded his mind; "If I could free my hands, I might throw off the noose and spring into the stream. By diving I could evade the bullets and, swimming vigorously, reach the bank, take to the woods and get away home. My home, thank God, is as yet outside their lines; my wife and little ones are still beyond the invader's farthest advance.", as he mentions his wife and kids it reveals that he was a caring father and spouse.

The next part of the story brought his adventures and daring side out as he had fallen into the stream and the rope around his had broken, despite the pain he had escaped the men who had pointed their guns at him and had tried to shoot him as he tried to dodge their bullets.

The sensory details in this story had the reader feeling as if he was right beside Peyton Farquhar, its highly detailed description of the setting had led my heart pounding until the very end. At the end when he finally finds his way home and he spots his wife, he thinks about how beautiful she is and he jumps in for a hug shows his love and admiration to his family.