Which is greater? $\large\frac{1}{2}$ of $\large\frac{6}{7}$ or $\large\frac{2}{3}$ of $\large\frac{3}{7}$

Question

( A ) $\large\frac{1}{2}$ of $\large\frac{6}{7}$
( B ) Cannot be determined
( C )$ \large\frac{2}{3}$ of $\large\frac{3}{7}$
( D ) None of these