A researcher conducts a well-designed study to compare a sample mean to a known population mean and uses alpha=.05, two-tailed. She finds a z-test of 1.98, p-value=.048. What should she conclude?
a. The 95% confidence interval of the z-statistic will contain zero
b. The conclusion cannot be made without knowing the direction of the alternative hypothesis
c. Data support the alternative hypothesis
d. She fails to reject the null hypothesis