What are the sequences of the investigator's forward and reverse primer? Enter them 5′ to 3′.

a) 5'-ATCG-3', 3'-TAGC-5'
b) 5'-GCAT-3', 3'-CGTA-5'
c) 5'-CTAG-3', 3'-GATC-5'
d) 5'-TACG-3', 3'-ATGC-5'