Explanation:

- A and B together complete 36% of the work in 9 days. Therefore, they can finish the entire work in $\frac{100}{36}\times 9=25$ days.

- B alone finishes the work in 30 days. Therefore, B's one-day work = $\frac{1}{30}$.

- A and B's one-day work combined is $\frac{1}{25}$.

- Using the formula $(A+B)-B=A$, A's one-day work = $\frac{1}{25}-\frac{1}{30}=\frac{1}{150}$.

- This implies A alone will take 150 days to complete the work.

So, the correct option is:

Option 3: 150 days