The value of \(\left( {1 - \frac{1}{2}} \right)\left( {1 - \frac{1}{3}} \right)\left( {1 - \frac{1}{4}} \right)......\left( {1 - \frac{1}{{40}}} \right)\) on simplification is

• A. 0
• B. \(\frac{1}{{20}}\)
• C. \(\frac{1}{{30}}\)
• D. \(\frac{1}{{40}}\)