Answer from cs61c-cm (Christopher Marcellino 15775059) for Question 1
B is the only true answer. Since when a block is found in the first-fit search that is larger than the requested space. The end of the block is used for the allocation and the begining simply has its size adjusted. This can keep the number of blocks unchanged. It is possible that the number of blocks may decrease if a whole block is allocated, but it can never increase.