Researchers are investigating the effectiveness of leg-strength training on cycling performance. A sample of 7 men will be selected to participate in a training program that lasts for one month. Peak power during cycling will be recorded for each man both before training and after training. The mean difference in times will be used to construct a 95 percent confidence interval for the mean difference in the population.When all other things remain the same, which of the following statements about the width of the interval is correct?A) The interval will be narrower if 15 men are used in the sample.B) The interval will be wider if 15 men are used in the sample.C) The interval will be narrower if 5 men are used in the sample.D) The interval will be narrower if the level is increased to 99% confidence.E) The interval will be wider if the level is decreased to 90% confidence.