Which of the following has the potential to cause poor speech intelligibility?

• A. Echoes
• B. Reverberation
• C. Low S/N ratio
• D. All of the above

Answer: (D)

Speech intelligibility suffers when the sound signal arrives in ways that distort or mask the message. Echoes create delayed copies of the voice that arrive after the direct sound, causing overlapping sounds that blur syllables and can make it hard to understand what’s being said. Reverberation is the buildup of many reflections in a space, so energy from speech lingers and blends with upcoming sounds; this tailing reduces the clarity of rapid speech cues like consonants, making words run together. A low signal-to-noise ratio means background noise is strong relative to the speech, masking parts of the message and forcing the listener to work harder to extract meaning. Because any of these factors can degrade understanding, all of the above can cause poor speech intelligibility.