Right option is (a) 300–3000 Hz
Easy explanation: Speech audiometry normally allows measurements to be made within the frequency range of 300–3000 Hz. Pure-tone audiometers usually generate test tones in octave steps from 125 to 8000 Hz, the signal intensity ranging from –10 dB to +100 dB. Some patients may have impaired high frequency response due to high intensity level occupational noise at 4000 or 6000 Hz.
