Which of the following correctly describes how the width of a confidence interval for a population mean changes when the population standard deviation is known? O There is no change if just the sample size increases. O The interval widens if the sample size stays the same and confidence level decreases. O The interval narrows if the sample size increases and confidence level stays the same. O The interval narrows if the sample size decreases and confidence level stays the same. O The interval widens if the sample size increases and the confidence level stays the same.