You want to compare several page replacement algorithms, so you can determine which algorithm is best. For that you perform an analysis of the algorithm: Optimal, FIFO, LRU and Clock. You use the following case: use 4 memory frames in the order of Page Address Stream that requires memory: 3 2 1 4 5 2 3 4 2 1. Count the number of page faults occurs for each algorithm, and based on the results of your analysis, which algorithm is best in this case? Explain.