What generally happens when black is added to a cool colour?

Correct answer: A darker shade will form

The governing concept is the change of value caused by mixing a colour with black. Black lowers the lightness of a cool colour such as blue or green, producing a darker version called a shade. Therefore, option A is correct. White would create a lighter tint, so option B describes the opposite process. Adding black does not change the colour family from cool to warm, and it cannot turn an existing colour into a primary colour.