Income tax urgent query

An Assessee is a senior citizen having 8 lakh Income last year. The Assessee has bank interest of 8.5 Lakhs this year and hence will have to pay Tds @ 10 % amounting to 85,000. According to the new 15 H form guidelines should the Assessee pay tax on 2 lakhs (8L -5L-1L 80C) @ 20% amounting to 40000 or should he submit 15 H eventhough his income last year is 8L and claim income tax refund of 45000(85000-40000). Which option is better considering the opportunity cost?