Six books labeled as A, B, C, D, E, and F are placed side by side. Books B, C, E, and F have green covers while others have yellow covers. Books A, B, and D are new while the rest are old volumes. Books A, B, and C are law reports while the rest are medical extracts. Which two books are old medical extracts and have green covers?

• A. B and C
• B. E and F
• C. C and E
• D. C and F