Answer:
4. the next best thing given up. the price of a new opportunity that arises.
Explanation:
The opportunity cost is the cost we incurr when we choose something instead of other alternatives. To put it more simply: it the cost of the alternatives that we give up when we choose something.
For example, suppose I have $1,000 and have two options: 1) putting the money on a savings account that pays 2% annual interest 2) buying and Iphone X.
If I put the money on the savings account, the opportunity cost is the lack of enjoyment that and Iphone X would have provided me.
And if I bought the Iphone X, the opportunity cost would be the lack of interest earned on the deposit.