There are four candles which can burn for 5 hours, 4 hours, 3 hours and 2 hours respectively. All of them are lighted at the same time. They are kept lighted till the time 3 candles are finished. If the cost of lighting each candle is 1.5 per hour, what will be the total expenditure?

• A. Rs.16.50
• B. Rs.18.00
• C. Rs.19.50
• D. Rs.21.00