Which lighting technique involves isolating acting areas with single spotlights?

The technique of isolating acting areas with single spotlights is known as focused lighting. This method involves directing a concentrated beam of light to illuminate a specific part of the stage or a particular actor. By using spotlights, the lighting designer can highlight important moments, create dramatic effects, and guide the audience's attention to where it is most needed.

Focused lighting is crucial in theatrical productions because it helps define space and mood, allowing for greater emphasis on character and action. It can be adjusted in intensity and angle to achieve the desired effect, making it a versatile tool in stage lighting design.

While other lighting options may serve different purposes—such as creating an overall ambiance or filling in shadows—they do not specifically pertain to the isolation of acting areas like focused lighting does.