If \(\sin \left( {A - B} \right) = \frac{1}{2}\) and \(\cos \left( {A + B} \right) = \frac{1}{2}\), where A > B > 0° and A + B is an acute angle, then the value of A is:

• A. 30°
• B. 60°
• C. 45°
• D. 15°