A mixture contains alcohol and water in the ratio 4 : 3. If 5 litres of water is added to the mixture, the ratio becomes 4 : 5. The quantity of alcohol in the given mixture is -

• ক 8 litres
• খ 10 litres ✅ সঠিক উত্তর
• গ 12 litres
• ঘ 15 litres