An IS auditor discovers that developers have operator access to the command line of a production
environment operating system. Which of the following controls wou Id BEST mitigate the risk of
undetected and unauthorized program changes to the production environment?

A.
Commands typed on the command line are logged

B.
Hash keys are calculated periodically for programs and matched against hash keys calculated for
the most recent authorized versions of the programs

C.
Access to the operating system command line is granted through an access restriction tool with
preapproved rights

D.
Software development tools and compilers have been removed from the production environment

Explanation:
The matching of hash keys over time would allow detection of changes to files. Choice A is incorrect
because having a log is not a control, reviewing the log is a control. Choice C is incorrect because
the access was already granted-it does notmatter how. Choice D is wrong because files can be
copied to and from the production environment.