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We hear an echo due to

Options

  1. ARefraction of sound waves
  2. BReflection of sound waves
  3. CDiffraction of sound waves
  4. DResonance due to sound waves

Correct answer

B. Reflection of sound waves

Step-by-step solution

An echo is the phenomenon of hearing a sound again after it has been reflected from a distant obstacle such as a wall, mountain, or building. Therefore, an echo is caused by the reflection of sound waves. Answer: Reflection of sound waves

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