What is the value of $$c^{2} $$ in the given figure, where the radius of the circle is ‘a’ unit.

A

$$c^{2} = a^{2} + b^{2} - 2ab cos θ$$

B

$$c^{2} = a^{2} + b^{2} - 2ab sin θ$$

C

$$c^{2} = a^{2} - b^{2} + 2ab cos θ$$

D

None of these