$\sin 54^{\circ}=\frac{1}{4}(1+\sqrt{5})$ হলে $\cos 36^{\circ}$ এর মান-

$\frac{1}{4}(1+\sqrt{5})$

$\frac{1}{4}(1-\sqrt{5})$

$\frac{1}{4}(\sqrt{5}-1)$

$\frac{1}{4}(-1-\sqrt{5})$