Let \( S = 2 + \frac{6}{7} + \frac{12}{7^{2}} + \frac{20}{7^{3}} + \frac{30}{7^{4}} + \ldots \). Then \( 4S \) is equal to
\( \left( \frac{7}{3} \right)^{2} \)
\( \frac{7^{3}}{3^{2}} \)
\( \left( \frac{7}{3} \right)^{3} \)
\( \frac{7^{2}}{3^{3}} \)