Which description best characterizes the primary purpose of an oscilloscope?

• A. To observe real-time voltage waveforms
• B. To measure static resistance
• C. To generate signals
• D. To regulate power supply

Answer: (A)

An oscilloscope is used to visualize how voltage changes over time. It plots voltage on the vertical axis and time on the horizontal axis, so you can see the shape of a waveform, its amplitude, frequency, and any changes as the signal evolves. This lets you observe real-time waveforms, catch transient spikes, measure how long events take to occur, and analyze characteristics like duty cycle and phase. That focus on watching how signals vary over time differentiates the scope from other tools: static resistance is typically measured with a multimeter, generating signals is the job of a function generator, and regulating a power supply is done by the supply itself. So, the best description is that an oscilloscope observes real-time voltage waveforms.