A researcher is testing the hypothesis that a population mean is equal to zero. From a sample with 64 observations, the researcher calculates a sample mean of -2.5 and a sample standard deviation of 8.0. At which levels of significance should the researcher reject the hypothesis? 1% significance 5% significance 10% significance A) Reject Fail to reject Fail to reject B) Fail to reject Fail to reject Reject C) Reject Reject Reject D) Fail to reject Reject Reject