If the user selects an attributes value that has a price, how is the resulting product item price calculated?

In a configurable product, pricing is defined both in the product Base price, and also in the price field of some user selected Attribute values.

If the user selects an attributes value that has a price, how is the resulting product item price calculated?
A . Product item price will be equal to product Base Price only.
B . Product Item price will be equal to product Base price plus the price of the selected Attribute only if It is a line item
C . Product item price will be equal to product Base price plus of the selected Attribute only if it of the pricing formula.
D . Product Item price will be equal to product price plus the price of the selected Attribute only if it is not a line item.

Answer: C