When troubleshooting an electronic circuit, an unreliable high resistance "cold" solder joint can be located with the aid of an ohmmeter. Once the problem has been located, what should be done?

Correct Answer: Option A — reheat connection with a soldering tool and recheck with an ohmmeter

A cold solder joint exhibits high contact resistance and intermittent continuity. Per standard electrical maintenance practices, reflowing the joint with a proper soldering tool re-establishes a robust metallic bond, which must be verified using an ohmmeter to confirm zero resistance.