What feature in After Effects allows layers to respond to audio frequencies?

The Audio Spectrum Effect is a powerful tool in After Effects that enables layers to visually respond to audio frequencies. This effect creates a dynamic visual representation of audio frequencies, allowing you to generate graphics that change in real-time according to the sound’s amplitude and frequency. By applying this effect to a layer, you can create animations that pulsate, morph, or move in sync with specific audio tracks, enhancing the overall impact of your project.

The Audio Spectrum Effect can be particularly useful for music videos or presentations where visual representation of sound enhances the viewer's experience. It allows creators to associate sound with motion visually, transforming sound waves into vibrant graphical displays that add depth and excitement to the visual content.

The other options, while related to audio, do not offer the same capability in terms of dynamic interaction with audio frequencies as the Audio Spectrum Effect does. Other effects might focus on different aspects of sound visualization but do not react in real-time to audio as effectively as this specific effect.