Question

The sound caused by can harm human ears.

• A. aeroplane
• B. mixer grinder
• C. whispering
• D. singing birds

Answer 1

The correct option is A aeroplane

Aeroplanes results in loud sounds with loudness of more than $140\text{dB}$ which can cause damage to human ears when exposed for a long time.
Whispering, singing birds fall under or around $80\text{dB}$ and are not dangerous to human ears at all.