If a Correlated-Groups T Test and an Independent-Groups T Test

Multiple Choice

If a correlated-groups t test and an independent-groups t test both have df=16, which experiment used more participants?​

A) They both used the same number of participants (n=18) .
B) They both used the same number of participants (n=17) .
C) The correlated-groups t test used more participants.
D) The independent-groups t test used more participants.