Which of the following statements correctly compares the t-statistic to the z-score when creating a confidence interval? A. The value of z relates to a normal distribution, while the value of t relates to a Poisson distribution. B. You can use t all the time, but for n 30 there's no need, because the results are almost identical if you use t or z.

C. Using t is easier because you do not have to worry about the degrees of freedom, as you do with z. D. Use t when the sample size is small, and the resulting confidence interval will be narrower.