What is a characteristic feature of E-TRACE?

The selection of web-based tracking of purchase/use history as a characteristic feature of E-TRACE is accurate because E-TRACE is designed primarily to assist law enforcement in tracing the history of firearms. This involves tracking the sale and transfer of firearms from manufacturers to retailers and ultimately to purchasers. By utilizing a web-based interface, law enforcement agencies can access a central database that consolidates this information, allowing for efficient querying and analysis of firearms' purchase and use histories. This web-based tracking capability is essential for investigations into firearm-related crimes and helps in establishing links between firearms and criminal activity.

Real-time tracking of firearms is not a feature of E-TRACE, as it primarily focuses on historical data rather than active monitoring. Similarly, while offline data collection might be part of the broader data-gathering process, E-TRACE's primary function emphasizes web-based access to existing data. Immediate law enforcement notifications are not a core characteristic of E-TRACE either; the system is structured to provide access to data rather than to send alerts in real-time. Thus, the focus on tracking purchase and use history highlights the essential role E-TRACE plays in firearm investigation and traceability efforts.