Which statement best describes how bit depth affects audio quality?

• A. Higher bit depth reduces the need for compression.
• B. Higher bit depth reduces file portability.
• C. Higher bit depth has no impact on audio quality.
• D. Higher bit depth generally improves audio quality by increasing dynamic range.

Answer: (D)

Bit depth controls how finely we can represent the amplitude of each audio sample. More bits provide more possible levels, so the quantization steps become smaller and the quantization noise decreases. This means the quieter details and the loud peaks can be reproduced more accurately, improving overall clarity. In practical terms, each extra bit adds about 6 dB to the dynamic range, so going from 16-bit to 24-bit dramatically expands the range between the quietest and loudest parts. That’s why higher bit depth generally improves audio quality by increasing dynamic range. The other ideas aren’t about quality: compression needs are separate from bit depth, and saying there’s no impact ignores the clearer, more detailed representation that comes with more bits.