In information systems, what is an “audit trail”? (Focus on data processing: tracing transactions step by step from source through processing to their effect on accounts.)

Introduction / Context:
An audit trail is central to accountability in computerized systems. It enables internal and external auditors to follow the lifecycle of a transaction—from initial capture to final posting—thereby verifying accuracy, detecting fraud, and supporting compliance. Understanding the exact definition distinguishes auditing mechanisms from generic data concepts.

Given Data / Assumptions:

• The system records the sequence of processing steps.
• Auditors need to trace transactions affecting accounts or records.
• We are differentiating an audit trail from unrelated data terms.

Concept / Approach:
An audit trail provides chronological records linking source documents, transformation steps, exception logs, and final postings. It is usually immutable, time-stamped, and access-controlled, facilitating reconciliation and forensic analysis. This trail is not the same as data definitions or grouped data elements; it is specifically about traceability.

Step-by-Step Solution:
Identify the option that emphasizes step-by-step traceability.Confirm it allows following all transactions that impact a given account or record.Select that option as the precise definition of audit trail.

Verification / Alternative check:
During an audit, sampling a transaction and being able to walk from ledger impact back to source invoice (and forward again) demonstrates a functioning audit trail.

Why Other Options Are Wrong:
Option B describes an attribute, not traceability. Option C describes a record or composite field (e.g., a tuple), again not traceability. Option D cannot be correct because B and C are not definitions of audit trail. Option E is wrong because a correct definition exists (option A).

Common Pitfalls:
Confusing change logs with fully linked audit trails; a proper trail ties identities, timestamps, actions, and before/after values to source and destination artifacts.

Final Answer:
a feature of data processing systems that allows study of data as processed step by step so an auditor can trace all transactions affecting an account