Explanation:

- Option 1: Profits are not equal. This can be a reason for using the weighted average method, but it’s not the primary reason.

- Option 2: Profits show a trend. The weighted average method is particularly used when profits show a trend, giving more weight to recent profits which better reflect future earnings potential.

- Option 3: Profits are fluctuating. While fluctuating profits might suggest another method, if there's a trend in the fluctuation, the weighted method can be apt.

- Option 4: None of the Above. This is not correct, as option 2 suits the question.

Correct Answer: Option 2 (Profits show a trend)