The declared rate of return compounded semi annually equivalent to the effective rate of return 10.25% per annum is:

10% p.a.

The correct answer is Option (3) → 10% p.a.

Let the nominal rate convertible semi-annually be $r$.

Effective annual rate $=10.25\% = 0.1025$.

For semi-annual compounding:

$\left(1+\frac{r}{2}\right)^2 = 1.1025$

Taking square root:

$1+\frac{r}{2} = \sqrt{1.1025} = 1.05$

$\frac{r}{2} = 0.05$

$r = 0.10$

$r = 10\%$

final answer: $10\%$ per annum compounded semi-annually