degree of freedom question

Question

A researcher wanted to test the effect of a new drug on reducing blood pressure. In the study, there were 35 participants. The researcher measured the participants’ blood pressure before and after the drug was administered. If we want to compare the mean blood pressure from the two time-periods with a two-tailed t test, how many degrees of freedom are there?

a.34

b.35

c.68

d.69

e.70

Not sure if i did this right but I was thinking the answer was A since DF= 35-1 = 34. Is that right

Answer 1

Yes. "sample" size is 35.