Satyam and Shubham together can do the twice of a work in 12 days and Pawan alone can do the same work in 5 days. Pawan is thrice as efficient as Satyam and Satyam takes 5 more days than Shubham to do the work alone. In how many days can Shubham alone do the work?

• A. 15 days
• B. 8 days
• C. 5 days
• D. 7 days
• E. 10 days