The MAIN purpose of a transaction audit trail is to:

A.
reduce the use of storage media.

B.
determine accountability and responsibility for processed transactions.

C.
help an IS auditor trace transactions.

D.
provide useful information for capacity planning.

Explanation:
Enabling audit trails aids in establishing the accountability and responsibility for processed transactions by tracing them through the information system. Enabling audit trails increases the use of disk space. A transaction log file would be used totrace transactions, but would not aid in determining accountability and responsibility. The objective of capacity planning is the efficient and effective use of IT resources and requires information such as CPU utilization, bandwidth, number of users, etc.