दिए गए विकल्पों में से, ध्वनि तरंगें निम्नलिखित में से किस माध्यम में सबसे तेज़ गति से यात्रा करती हैं?

A 'One-third Octave Band' is defined as a frequency band in which the upper cutoff frequency (fu) and lower cutoff frequency (fL) are related by:

Assertion (A): A-weighting network is widely used in environmental noise measurement. Reason (R): It approximates the frequency response of the human ear at low sound levels.