Dr. Fred Krueger wants to determine whether students' attendance at a review session would result in higher exam scores on the upcoming exam. So, he provides a review session for one section of Psychology 1A, but not for the other section, and decides to compare the exam scores of these two sections. When he compares the mean scores from the two groups, he finds that they are not statistically different from one another. In fact, both groups of students did extremely well on the exam. It appears that Dr. Krueger's measure has produced a O floor effect O ceiling effect. O reactive effect. O response set.