Respuesta :
In my opinion the answer would be opportunity cost. Though the movie was downloaded free in the internet the $4 dollar charge was due to the opportunity cost spent. Opportunity cost is when a person has to give up a gain to have an alternative gain in return.
Charlotte paid $4 for a movie download. The monetary amount is the download's: Accounting cost
Opportunity cost only happen when a person choose to do an economic action by sacrificing another option. which ruled out option 2.
Retail price is the price of the product in retail store. Since the purchase is conducted online, this ruled out option 3.
This will leave us with option 1