A process running on a system with demand-paged virtual memory generates the following reference string (sequence of requested pages): 4, 3, 6, 1, 5, 1, 3, 6, 4, 2, 2, 3. The operating system allocates each process a maximum of four page frames at a time. What will be the number of page faults for this process under each of the following page replacement policies?

a. LRU

b. FIFO

c. LFU (with FIFO as tiebreaker)