The chart shows the results of a study on stress reduction techniques. A map titled Effects of Techniques on Stress and Anxiety shows techniques on the horizontal axis and effect size (standard deviations) on the vertical axis. Concentration or contemplation resulted in negative 0.3. Other techniques resulted in negative 0.42. Transcendental meditation resulted in negative 0.8. A student wants to give his anxious friend advice on reducing stress. Based on the chart, what stress reduction technique should he recommend? exercising daily talking with friends transcendental meditation concentration or contemplation