Cross-cutting in film editing refers to:

Cross-cutting in film editing is a technique that involves editing two or more events that are happening simultaneously but in different locations. This method allows filmmakers to build tension, develop parallel storylines, and create a more dynamic narrative by showing how different storylines interact or converge.

By cutting between these simultaneous actions, the audience is able to perceive the relationship between the events, often leading to a heightened emotional response or a sense of urgency. This technique is often used in action sequences, where cutting back and forth between events can ramp up excitement or suspense.

The other options do not accurately capture the essence of cross-cutting. For example, while combining multiple narrative threads is relevant, it does not specifically describe the simultaneous nature of the events involved in cross-cutting. Switching between different camera angles is a different aspect of film editing related to visual perspective rather than narrative timing. Finally, integrating music with visuals pertains to sound design rather than the specific action of cross-cutting in editing.