What aspect of speech does a spectrogram represent visually?

• A. Consonantal distinctions
• B. The rhythm of speech
• C. Frequency, intensity, and duration of speech sounds
• D. Speech clarity

Answer: (C)

A spectrogram visually represents how the frequency content of speech changes over time. Time runs left to right, frequency runs bottom to top, and the darkness or color at each point shows how strong each frequency is at that moment. This means you can see which frequencies are present, how loud they are, and how long they last. Those three aspects—frequency, intensity, and duration—are exactly what a spectrogram encodes. The other ideas aren’t what a spectrogram directly shows: it’s not a labeled map of consonant types, nor a direct measure of speech rhythm as a beat pattern, nor a measure of how clear or intelligible speech is. It’s a snapshot of the acoustic spectrum evolving over time.