Which of the following describes extension in the SEE (statement, extension, elaboration) technique? A. add information that further explains or defines the main idea ... B. Restate the idea. C. Sum up or repeat the idea. D. State the main idea of the paragraph.

The correct option is A.

The SEE technique is used in essay writing to provide a better understanding and to enhance clear communication of the information that one is trying to pass across in the essay. The method involves stating the the main idea of the essay and adding supporting information that further explain the main idea of the essay.

"Add information that further explains or defines the main idea" is the one among the following choices given in the question that describes extension in the SEE (statement, extension, elaboration) technique. The correct option among all the options that are given in the question is the first option or option "A".