A New Sales Training Program Has Been Instituted at a Rent-To-Own

A new sales training program has been instituted at a rent-to-own company. Prior to the training, 10 employees were tested on their knowledge of products offered by the company. Once the training was completed, the employees were tested again in an effort to determine whether the training program was effective. Scores are known to be normally distributed. The sample scores on the tests are listed next. Use pre-test score as µ₁ for population 1 and post-test score as µ₂ for population 2, or µ_D as the difference calculated as pre-test score minus post-test score. Which of the following is the correct conclusion for the test at α = 0.05?

A) Given the critical value 1.645, we conclude that training increases scores on average.
B) Given the critical value 2.015, we conclude that training increases scores on average.
C) Given the critical value −2.015, we conclude that training increases scores on average.
D) Given the critical value −1.645, we conclude that training increases scores on average.