What component aggregates data from multiple sources within an ICS?

The Data Historian is the correct choice because it serves as a centralized storage system that aggregates data from various sources within an Industrial Control System (ICS). This component is essential in monitoring, analyzing, and managing data relating to industrial processes over time. It collects both real-time and historical data from devices such as sensors, controllers, and other monitoring equipment.

By consolidating this data, a Data Historian enables organizations to perform analysis, generate reports, and make informed decisions regarding operational efficiency and process optimization. The ability to store large volumes of data and provide insights into system performance is critical for organizations that rely on ICS.

The other components, while integral to the functioning of an ICS, do not perform the same role as a Data Historian. Modbus is a communication protocol used for transmitting data between devices. A Programmable Logic Controller (PLC) is responsible for automated control of processes but does not aggregate data from multiple sources. Fieldbus refers to a network system for industrial devices but does not serve as a storage or aggregation mechanism.