Electron flow is measured in which unit?

The correct answer is amps. Electron flow refers to the actual movement of electrons through a conductor, and this movement is quantified as electric current. The unit of measurement for electric current is the ampere, often shortened to "amp." This indicates how much charge is flowing through a circuit over a specific period of time, essentially capturing the rate of electron flow.

Understanding the other options provides further context: volts measure electric potential difference, which indicates the force that pushes electrons through a circuit; ohms measure resistance within the circuit, or how much a material opposes the flow of current; and watts quantify power, which is the rate at which electrical energy is consumed or produced in a circuit. Each of these units plays a critical role in the understanding of electrical systems, but when specifically discussing the flow of electrons, amps is the appropriate unit of measurement.