In the arrangement shown in figure below, the ends P and Q of an stretchable string move downwards with uniform speed u. Pulleys A and B are fixed. Mass M moves upwards with a speed

• A. \[2u\cos \theta \]
• B. \[u\cos \theta \]
• C. \[\frac{2u}{\cos \theta }\]
• D. \[\frac{u}{\cos \theta }\]