What is the value of the cut-off frequency? \text { a. } 0.6 \mathrm{KHz}+/-0.1 \mathrm{KHz} \text { b. } 2.0 \mathrm{KHz}+/-0.1 \mathrm{KHz} \text { c. } 1.0 \mathrm{KHz}+/-0.1 \mathrm{KHz} \text

{ d. } 1.6 \mathrm{KHz}+/-0.1 \mathrm{KHz}