$4\mathrm{.}1\mathrm{.}6$ Miriam took a bond of R$250000$ over a $25$ year period at $10\%$ per annum. What will the customer$$s outstanding balance be after $12$ years if she makes monthly instalments?

a$)$ R$1654,43$

b$)$ R$52085,57$

c$)$ R$197913,98$

d$)$ R$275046,43$