While an audit is being conducted, which of the following could cause management and the auditors to change the original plan in order to continue with the audit?

When the actual costs of conducting an audit exceed the budgeted amount, management and auditors must re-evaluate the audit plan to either secure additional funding, reduce the audit scope, or adjust the timeline. This financial constraint directly impacts the feasibility and continuation of the audit as originally planned.

Impact on systems is a technical risk during an audit, but it's typically managed through careful planning and testing, not a primary driver for changing the audit plan itself unless it prevents the audit from proceeding entirely.

Regulatory changes might impact compliance requirements and the scope of future audits, but they do not typically cause a change to an audit plan already in progress unless the change directly invalidates the audit's objectives.

Software version changes are technical details that an audit might evaluate, but they are unlikely to cause a fundamental change to the audit plan unless they introduce a critical vulnerability or compatibility issue that prevents audit tools from functioning.