Which of the following is the largest fraction ? $${\text{ }}\frac{6}{7},$$ $$\frac{5}{6},$$ $$\frac{7}{8},$$ $$\frac{4}{5}$$

• A. $\frac{6}{7}$$
• B. $\frac{4}{5}$$
• C. $\frac{5}{6}$$
• D. $\frac{7}{8}$$