The correct answer is D. A worker wage is Rs. 15 per hour.
A fixed cost is a cost that does not change in total regardless of the number of units produced or sold. Examples of fixed costs include rent, insurance premiums, and salaries.
A worker wage is not a fixed cost because it is a variable cost. A variable cost is a cost that changes in total in direct proportion to the number of units produced or sold. For example, if a company produces 100 units and each unit costs Rs. 15 to produce, then the total cost of production is Rs. 1,500. If the company produces 200 units, then the total cost of production is Rs. 3,000.
The other options are fixed costs because they do not change in total regardless of the number of units produced or sold. For example, if a company rents a building for Rs. 1,000 per month, then the total cost of rent is Rs. 1,000 per month, regardless of whether the company produces 100 units or 200 units.