What is the primary color found in the self variety of Mini Rex?

The primary color found in the self variety of Mini Rex is black. In rabbit color genetics, the "self" variety refers to a color pattern where the entire coat is of a solid color without any markings. The self variety can include various solid colors, but black is notably one of the standard colors recognized in show rabbits, including the Mini Rex breed. Black rabbits exhibit a deep, rich color that is often desired in showmanship due to its striking appearance.

The other colors mentioned, such as chinchilla, tan, and white, represent different coat patterns or color varieties in rabbits. Chinchilla refers to a variety with a specific shading pattern, tan includes a specific marking that is not solid, and white may indicate a loss of pigment but does not represent the primary solid color for the self variety. The solid nature of the black in the self variety makes it an ideal choice for this question.