What amount of washing soda and kerosene oil should be added in water to make a solution to clean the cooling system?

• A. 2 kg water and 0.5 kg kerosene oil
• B. 2.5 kg water and 1.5 kg kerosene oil
• C. 1 kg water and 0.5 kg kerosene oil
• D. 1.5 kg water and 2.5 kg kerosene oil