Asset tags are used to assign a unique identification to each piece of hardware, which allows for effective tracking and management of physical assets within an organization. These tags often contain barcodes or RFID chips that can be scanned to retrieve important asset information, hence why asset tags are the correct answer. Serial numbers, while unique to each device, are designated by the manufacturer and could be hard to track internally without a comprehensive database. MAC addresses are unique identifiers assigned to network interfaces, but they are not typically used for physical asset tracking. Service tags often refer to manufacturer-specific identification, which like serial numbers, isn't designed primarily for internal asset management and tracking.