To solve this problem, we need to understand the concept of profit percentage and how it is calculated. The profit percentage is calculated by dividing the profit by the selling price and multiplying by 100.

Let's assume the selling price of the article is $S. According to the question, the man makes a profit of 25% of the selling price. So, the profit he makes is 25% of S, which can be written as 0.25S.

Now, let's calculate the profit percentage. Profit percentage = (Profit / Selling Price) * 100. In this case, the profit is 0.25S and the selling price is S. Substituting these values, we get:

Profit percentage = (0.25S / S) * 100 = 0.25 * 100 = 25

Therefore, the man's profit percentage is 25%.

Explanation:

- Introduction: Explain the concept of profit percentage and how it is calculated.
- Given information: State the selling price of the article and the profit percentage.
- Calculation: Calculate the profit made by the man using the given information.
- Formula: Explain the formula for calculating profit percentage.
- Substitution: Substitute the values into the formula and simplify the expression.
- Result: State the final result, which is the man's profit percentage of 25%.

In conclusion, the man's profit percentage is 25%. Therefore, the correct answer is option C) 25.