Probably the most important issue in implementing file storage is keeping track of which disk blocks go with which file. Which of the statements below are true about the methods used for that? I the simplest allocation scheme is to store each file as a contiguous run of disk blocks: the advantage of this method is that there is no disk fragmentation ii we can store each file as a linked list of disk blocks, using the first word in each block as a pointer: a disadvantage of this method is that random access is extremely slow (resolved by placing the pointers in a table in memory) iii the File Allocation Table (FAT) scales well to large disks iv we can associate each file with a data structure called an i-node (index node), which lists the attributes and disk addresses of the file's blocks: this method occupies less space than the FAT i, ii, and iii ii, iii, and iv ii and iv