Explanation:

- Let's use some algebra here. Assume:

- C takes x days to do the work alone.

- Therefore, A takes 3x days (thrice as much time as C).

- B takes 1.5x days (as A takes twice as much time as B).

- Working together, they complete the work in 2 days, so:

\(\frac{1}{3x} + \frac{1}{1.5x} + \frac{1}{x} = \frac{1}{2}\).

- Simplify this equation. Find a common denominator and solve for x:

\(\frac{1}{3x} + \frac{2}{3x} + \frac{3}{3x} = \frac{1}{2}\).

- This gives you:

\(\frac{6}{3x} = \frac{1}{2}\).

- Solving for x, we get:

\(x = 4\).

- B takes 1.5x days, so B takes \(1.5 \times 4 = 6\) days.

- So, B will take 6 days to complete the work alone.

- Option 2: 6 is correct.

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