The correct answer is: B. White, black
White is a light color that is often used as a background color because it is easy to see text on. Black is a dark color that is often used for text because it is easy to read.
Option A is incorrect because blue and pink are both light colors. Light colors can be difficult to read text on, so they are not typically used as background colors.
Option C is incorrect because black and white are both dark colors. Dark colors can be difficult to read text on, so they are not typically used as text colors.
Option D is incorrect because pink and blue are both light colors. Light colors can be difficult to read text on, so they are not typically used as background colors.