The correct answer is: B. Variable cost
A variable cost is a cost that changes in proportion to the changes in the level of output. In other words, it is a cost that varies directly with the volume of production. Raw materials are a good example of a variable cost, because the more products you produce, the more raw materials you will need to purchase.
Fixed costs, on the other hand, are costs that do not change in proportion to the changes in the level of output. They are costs that remain the same regardless of the volume of production. Examples of fixed costs include rent, insurance, and depreciation.
Opportunity cost is the cost of something that you give up when you choose one option over another. For example, if you choose to go to college, you are giving up the opportunity to work full-time and earn money.
Short-term costs are costs that are incurred over a short period of time, such as a month or a quarter. Long-term costs are costs that are incurred over a longer period of time, such as a year or five years.
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