Concept:Gross profit is based on the selling price, so assume SP=100 and then calculate the cost price.Explanation:Let the selling price be SP=₹100.Gross profit =26% of SP=10026​×100=₹26.So, cost price CP=SP−Profit=100−26=₹74.Now, 34% of CP=10034​×74=₹25.16.Since SP=₹100, this amount equals 25.16% of the selling price.Answer:25.16%, i.e., Option B.