$$\frac{3}{4}\left(1 + \frac{1}{3}\right)\left(1 + \frac{2}{3}\right)\left(1 - \frac{2}{5}\right)\left(1 + \frac{6}{7}\right)\left(1 - \frac{12}{13}\right)$$ is equal to

A

$$\frac{2}{13}$$

B

$$\frac{1}{7}$$

C

$$\frac{1}{6}$$

D

$$\frac{1}{5}$$