Opportunity cost in economics refers to the value of the next best alternative that must be given up to obtain something else. Ifthe consumer chooses to buy the pair of shoes costing 10,theywillbeleftwithnomoney,thusgivinguptheopportunitytobuythehandbagandjewellerywhichtogethercost10. The other options are not correct because the dress costs $20 which is morethan the consumer's budget, and the dress and jewellery together also cost more than the consumer's budget.