Which of the following statements is correct?

I Variable costs can be defined as the costs that vary directly with sales II The change in variable costs that occurs when production is increased by one unit is referred to as the marginal cost. III Variable costs can be defined as the costs that remain constant over the short run. IV Fixed costs can be ignored in scenario analysis since they are constant over the life of a project.

Group of answer choices

I and II only

I, II, and IV only

II, III, and IV only

II and IV only

I, II, and III only