The correct answer is C. 4 times.
The stock turnover ratio is a measure of how many times a company sells its inventory in a year. It is calculated by dividing the cost of goods sold by the average inventory. In this case, the cost of goods sold is Rs. 2,20,000, the opening stock is Rs. 50,000, and the closing stock is Rs. 60,000. The average inventory is therefore (50,000 + 60,000) / 2 = Rs. 55,000. The stock turnover ratio is therefore 2,20,000 / 55,000 = 4 times.
Option A is incorrect because the stock turnover ratio is not 2 times. The stock turnover ratio is 4 times.
Option B is incorrect because the stock turnover ratio is not 3 times. The stock turnover ratio is 4 times.
Option D is incorrect because the stock turnover ratio is not 5 times. The stock turnover ratio is 4 times.