Final answer:
The contribution margin is the difference between sales revenue and variable costs.
Step-by-step explanation:
The correct answer is B) Sales minus variable costs. The contribution margin is a measure of the profitability of a product and represents the amount of revenue that is left after deducting the variable costs associated with producing that product.
For Scott Power, the contribution margin is the difference between the sales revenue it generates from selling batteries and the variable costs associated with producing those batteries.