Researchers investigated the effects of a new drug on blood pressure. They found that patients taking the drug lowered their blood pressure on average 15 mmHg more than patients taking the placebo ( p-value = 0.013). If the pre-specified type I error rate the researchers are willing to tolerate was set at 5%, what can the researchers conclude regarding the null hypothesis that there is no difference between drug and placebo?

a. Not enough information to determine.

b.Accept the alternative hypothesis

c.Reject the null hypothesis

d.Accept the null hypothesis

e.Fail to reject the null hypothesis