Which component is critical in ensuring video and audio sync during editing?

Timecode plays a crucial role in ensuring video and audio synchronization during editing. It provides a numerical code that identifies specific frames in both the video and audio tracks. By assigning timecodes to these tracks, editors can precisely align audio and video elements at the exact moment they are supposed to occur.

When working with multiple audio sources or when syncing audio with footage shot separately (such as dialogue recorded on a separate device), timecode is essential. It allows editors to accurately match audio clips to corresponding video frames, ensuring that dialogue, sound effects, and music play in sync with the visual elements.

In contrast, while a leader is helpful for marking the beginning of a film and resolving certain issues during post-production, and resolution and frame rate dictate the quality and smoothness of the video playback, they do not directly address the synchronization of audio and video tracks in the editing process.