The correct answer is subject-by-subject organizational method. An essay organized in a subject-by-subject pattern first will present all the arguments related to A, and then will compare and/or contrast them to all arguments related to B. The arguments discussed for A should be presented in the same order for B. The organization of the paragraphs would be as follows:
Introduction
Paragraph topic A:
Point 1 about A
Point 2 about A etc.
Paragraph topic B:
Point 1 about B (with discussion about connections to A)
Point 2 about B (with discussion about connections to A) etc.
There are two ways to organize a comparison/contrast essay:
A) Block Approach. This organizational pattern is most effective when used on short essays,
such as in-class essays. The body of such an essay is organized by discussing one subject, point
by point, in complete detail before moving on to the next subject. The writer should select points
by which both subjects can be examined. The number of body paragraphs will be determined by
the number of points discussed in the essay.
B) Point-by-Point Approach. This organizational pattern is most effective when used on longer
essays, such as a comparison of two articles, short stories, or novels. The body of such an essay
is organized by discussing one point at a time and how it applies to each subject before moving
on to the next point. For long works, at least three points should be examined if not more.
