What type of meter can measure currents as low as a few milliamperes?

The correct answer is a clamp-on ammeter because this device is specifically designed to measure electrical current flowing through a conductor without the need to make direct electrical contact. Clamp-on ammeters can accurately measure both high and low current levels, including those as low as a few milliamperes.

This ability to measure low currents makes clamp-on ammeters particularly useful in various applications, such as troubleshooting electrical systems, where one might need to monitor small currents in order to assess the performance of circuits or devices.

Other devices listed, such as clamp-on voltmeters and clamp-on wattmeters, primarily focus on voltage and power measurements, respectively, and are not optimized for direct current measurement. A clamp-on multimeter can measure current, voltage, and resistance, but its primary design and most effective use revolve around providing a broader range of electrical measurements rather than exclusively targeting low current detection.