The correct answer is 'D. Systems and data affected by the breach'. Including a detailed account of the systems and data affected is essential for understanding the full scope of the incident. This information is vital for management to comprehend the extent of the breach and to make informed decisions about how to proceed with containment, eradication, and recovery processes. 'A. A list of all employees in the company' is irrelevant to the scope of the incident. 'B. The company's total annual cybersecurity budget' does not directly relate to the specific incident scope. 'C. Percentage of network bandwidth utilized during the breach' may provide technical insight but does not effectively communicate the scope of the affected assets.