The minimum detectable sound for normal hearing is arbitrarily set at decibels. a. 5 b. 10 c. 25 d. 0

Generally a human can hear sounds in the range of 20-20,000 Hz, in terms of frequency. On the other hand, in terms of loudness, humans can safely hear sounds from 0 to 85 dB – though we can hear louder than that, it is generally advised that we wear protections for our hearing when listening to sounds that are louder than 85 dB at a prolonged period of time. Thus the correct answer from the option is: (D) 0 dB.