The correct answer is C. Rs 400.
Value added is the difference between the value of the output and the value of the inputs used to produce the output. In this case, the output is utensils worth Rs 1000, the inputs are copper worth Rs 500, wages paid of Rs 100, and other materials purchased of Rs 100. Therefore, the value added is:
$1000 – (500 + 100 + 100) = 400$
Option A is incorrect because it is the value of the output. Option B is incorrect because it is the value of the inputs. Option D is incorrect because it is the value of the inputs minus the value of the copper.