A can do a piece of work alone in 12 days. B is 20% more efficient than A, and C is 25% more efficient than B. In how many days can B and C together complete the work?

A

$$\frac{35}{9}$$ days

B

$$\frac{40}{9}$$ days

C

$$\frac{35}{7}$$ days

D

$$\frac{40}{7}$$ days