A study compared five different methods for teaching descriptive statistics. The five methods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam. We are interested in finding out if the average test scores are different for the different teaching methods.
The p-value of the test is 0.0168. What is the conclusion of the test?
A. At most two group means are significantly different from each other.
B. All five group means are significantly different from each other. C. All five group means are equal to each other.
D. Only two group means are significantly different from each other.
E. At least two group means are significantly different from each other.