Before playing the orchestra in a musical concert, a sitarist tries to adjust the tension and pluck the string suitably. By doing so, he is adjusting
frequency of the sitar string with the frequency of other musical instruments
The explanation for the correct option:
(C) frequency of the sitar string with the frequency of other musical instruments
The explanation for incorrect options:
(A) Intensity of sound only
(B) Amplitude of sound only
(D) Loudness of sound
Hence, option (C) is correct.