When selecting bench test equipment for troubleshooting and characterization, a good setup should generate known stimuli and also perform which complementary function on the circuit under test?

Introduction:
Effective electronic testing requires both stimulus and observation. While generators create known inputs, measurement instruments must sense what the circuit is doing in response. This question asks you to identify the complementary function to signal generation in a typical lab workflow.

Given Data / Assumptions:

• A technician has access to common bench gear (function generator, oscilloscope, multimeter, spectrum analyzer).
• Goal is verification and fault isolation on a circuit under test.
• We seek the essential counterpart to stimulus generation.

Concept / Approach:
Testing is a loop: apply known signals (stimulus) and measure the resulting voltages, currents, waveforms, and spectra (sensing/observation). Without sensing, you cannot validate behavior or diagnose issues. Therefore, the complementary capability is to sense or measure circuit conditions.

Step-by-Step Solution:
1) Identify stimulus tools: function generators and pattern sources.2) Identify sensing tools: oscilloscopes, DMMs, current probes, analyzers.3) Pair the two: stimulus in, observation out.4) Conclude that 'sense circuit conditions' is the correct complementary function.

Verification / Alternative check:
Standard troubleshooting flowcharts always include both injection and measurement steps—observe changes in node voltages/currents to localize faults.

Why Other Options Are Wrong:
Change circuit conditions: vague; any measurement changes loading slightly but the goal is observation, not arbitrary change.Inject signals: stimulus only; the question asks for the complementary function.Change signal frequencies: too specific and not a universal testing requirement.

Common Pitfalls:
Confusing tools that generate signals with those that measure them. Both are required for a closed-loop test strategy.

Final Answer:
sense circuit conditions