While in graduate school several years ago, I was part of a team proctoring a General Chemistry exam. During the course of the exam we observed that one student was using the K-Mart approach to obtain the answers to the questions.
What this student would do is read the exam question and then go shopping for the answer by looking at the answers the students in front of him and beside him were writing down. After carefully considering his choices, he took what he thought was the best answer.
Now, for one of the questions on the exam, one of the students next to our “shopper” wrote “I don’t know the answer to this question”. Our “shopper” wrote, “neither do I.”
shows the value of multiple choice, I guess