A new internal auditor is overwhelmed by the number of tasks they need to complete...

At the planning stage, auditors must organize and structure their work to ensure all necessary steps are covered. A checklist is the appropriate tool, as it provides a systematic list of tasks, reduces oversight, and helps manage workload. A control questionnaire (C) is used for assessing controls, and a fishbone diagram (D) is used for root cause analysis, not task management. Option A is irrelevant to planning execution.