A can do a job in 3 days less time than B. A works at it alone for 4 days and then B takes over and completes it. If altogether 14 days were required to finish the job, then in how many days would each of them take alone to finish it?
A. 17 days, 20 days
B. 12 days, 15 days
C. 13 days, 16 days
D. None of these