Indexed / grouped allocation is useful as : (A) It supports both sequential…
2023
Indexed / grouped allocation is useful as :
(A) It supports both sequential and direct access.
(B) Entire block is available for data.
(C) It does not require lots of space for keeping pointers.
(D) No external fragmentation.
Choose the correct answer from the options given below :
- A.
(A) Only
- B.
(B) and (C) Only
- C.
(B) Only
- D.
(A), (B) and (D) Only
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Correct answer: D
Final answer: The correct statements are: It supports both sequential and direct access; Entire block is available for data; No external fragmentation.
It supports both sequential and direct access: Indexed allocation uses an index block containing pointers to all file blocks, which allows direct access via the index and sequential traversal of blocks.
Entire block is available for data: Because pointers are stored in the separate index block, the individual data blocks hold only file data.
No external fragmentation: Blocks are allocated noncontiguously as needed, so indexed allocation does not suffer from external fragmentation that affects contiguous allocation.
Why the other statement is false: The claim that indexed allocation 'does not require lots of space for keeping pointers' is incorrect because the index block must hold one pointer per file block; for large files the index can require significant space.