Indexed file organization: what is in the master list? In an indexed file system, what does the master (data) list contain?

Introduction / Context:
Indexed file organization separates the master data (full records) from index structures (keys with pointers/record numbers). Understanding what lives in each component is vital for performance tuning and for reasoning about how lookups translate into record retrieval on disk.

Given Data / Assumptions:

• The “master list” refers to the main data file that holds complete records.
• The index is a separate structure containing key values and references to records.
• Record numbers (or addresses) enable direct access to the corresponding full record.

Concept / Approach:
The master list contains complete records with all fields. The index accelerates search by mapping keys to record identifiers (RIDs) or physical addresses. Once the index yields the record number, the system reads the corresponding full record from the master list.

Step-by-Step Solution:

Differentiate roles: master list = data; index = keys + pointers.Recognize that master records commonly have assigned record numbers/IDs.Reject options describing only keys; those define the index, not the master.Select “Full records, each with a record number assigned.”

Verification / Alternative check:
Descriptions of indexed-sequential files (ISAM/VSAM) consistently show master data separate from an index that stores keys and pointers to the full records.

Why Other Options Are Wrong:
Only sorted keys / only keys and record numbers: these describe the index, not the master file.

Both (b) and (c): mixing index content with master content is incorrect.

None of the above: incorrect because option (c) is accurate.

Common Pitfalls:
Assuming the master list is necessarily sorted by key; in many systems, organization may be by insertion order or by physical clustering independent of the index order.

Final Answer:
Full records, each with a record number assigned