Suppose we wish to test the hypothesis that the true population blood pressure is less than 165. This will require a one-sample t-test. Is this test a one-tailed or a two-tailed test?

one - tailed test.

Explanation:

One - tailed test -

It is a type of statistical test , where the area of distribution is only one sided , i.e. , the value can be either less than or greater than some specific value , and both can not be possible . It is referred to as the one - tailed test .

In this case , if the value lies in one- sided critical area , then the alternative hypothesis would be accepted not the null hypothesis .

Hence , from the given information of the question ,

The correct answer is one - tailed test .

answer; (c) all the above