The correct answer is D.
The cost has risen 1,000$ (comparting the 1500$ he had paid, with the 2500$ his friend has offered for the vacation, 1000$ is the amount he would miss if rejecting the offer plus the value of the activity he would do instead of the skiing vacation).
This cost rise represents the concept of opportunity cost. It is referred, when making a decision, to the value that is missed when rejecting the alternative option.
It is not rational for Eric to go skiing as the cost has risen to $1,000 plus the value of what he would have done if his friend wants to sell it at $2,500 due to the concept of opportunity cost.
In simple words, it is the cost of the next best alternatives that a person would have to sacrifice for getting the most appropriate benefit, it is the value of the next hied alternatives.
In the above case, it is not rational for Eric to skiing because now, the cost of the ticket is risen up by $1,000, and the value that Eric already paid in purchasing the ticket then it would be not beneficial to Eric to go for skiing. Therefore, it is good for Eric to accept the offer of her friend
Hence, option D is correct.
Learn more about the opportunity case, refer to:
https://brainly.com/question/17204577
