**Concept:** **The question tests on the basics of Rates(Time and Work)**

**Solution:**

Using the concept of Man Days where M1T1/W1=M2T2/W2

Let M1 = M, then M2 = 2M

T1 = 12 Days

Let W1 = W, then W2 = 0.5W

Therefore, we have M∗12/W=2*M∗T/0.5W

12M = 4MT

T = 3**Option E**