Following is not the feature/characteristic of Linked-List allocation of Files in a File system:

Explanation

Linked-list (chained) file allocation stores each file as a linked list of disk blocks, so there is no external fragmentation (statement 1 is a genuine, true feature). Because each block reserves a few bytes for the pointer to the next block, the usable data per block is not a clean power of 2 (statement 3 is true). The File Allocation Table (FAT) is precisely the well-known fix for linked allocation's weaknesses (statement 4 is true). However, linked allocation requires traversing the chain from the start to reach any block, so random access is actually very slow, not fast – statement (2) is false and is therefore the characteristic that does NOT belong to linked-list allocation.