The stator of a three-phase, 4 pole alternator accommodates a single-layer three-phase winding in 36 slots. If the coil span of the winding is 120 electrical degrees, then the distribution factor is:

• A. \(\frac{{\sin \left( {10} \right)}}{{3\sin \left( {30} \right)}}\)
• B. \(\frac{{\sin \left( {20} \right)}}{{3\sin \left( {60} \right)}}\)
• C. \(\frac{{\sin \left( {30} \right)}}{{3\sin \left( {10} \right)}}\)
• D. \(\frac{{\sin \left( {60} \right)}}{{3\sin \left( {20} \right)}}\)