Explanation:

Given that,
Rate of interest= 8.5 % per annum
time = 2 years
difference between the compound interest and simple interest=28.90 Rs.
Principle amount= x,
Now, we know that simple interest (SI) =
Substituting the values, 

                                                                                            R
Now, for compound interest Final amount (A) =P(1+100)^T
Now substituting the values, sxz

⇒ A = x(1.085) ²

⇒ A = x(1.085) ²

⇒ A = 1.1772x

Hence compound interest  CI = A − P = 1.177x − x = 0.1772x − − − − − − − −(ii)
From equation(i) and (ii)

CI − SI = 28.90

⇒ 0.170x − 0.177x = 28.90

⇒ 0.007x = 28.90

⇒ x = 0.007 =4128 Rs
Option will be the correct answer because it's the nearest value.