A can do a piece of work in 12 days, and B in 15 days. They work together for 5 days and then B left. The days taken A to finish the remaining work is :

[A]3 days

[B]5 days

[C]10 days

[D]121 days

**3 days**

Work done by A and B in 5 days

Remaining work

∴ Time taken by A

Hence option [A] is correct answer.