simplify the following equation$$ (1-{1 over3})(1-{1 over4})(1-{1 over5})......(1-{1 over n})$$

• A. $$ 1 over{n}$$
• B. $$ 2 over{n}$$
• C. $$ 2(n-1) over{n}$$
• D. $$ 2 over{n(n+1)}$$