For four years Gundo paid R$4500$ per month into vings account earning $6,9\%$ interest per year, compounded monthly. She then stopped her monthly payments, but left the money in the account to earn more interest. It still earned $6,9\%$ interest per year, but at that time the compounding periods changed to quarterly. The balance in the account $10$ years after she stopped her monthly payments, is

a$.$ R$188285,49.$

b$.$ R$216000,00.$

C$.R247935,56.$

d$.$ R$491413,14.$