Answer: -$25.

The correct answer is **B** (-$25). The profit to the seller of a call option is calculated as the call premium received minus the intrinsic value of the option at expiration. Here, the intrinsic value is the difference between the stock index at expiration (2,450) and the strike price (2,400), which is $50. Since the trader received a premium of $25, the profit is $25 - $50 = -$25. This aligns with the formula for the seller's profit: `Max(0, St - X) - C`, where `St` is the stock price at expiration, `X` is the strike price, and `C` is the premium received.

Author: LeetQuiz Editorial Team