Grandma minion's genotype for color blindness was: xcx xcxc xx xcy

The correct answer is XcXc.

Colorblindness is a X linked recessive trait that is marked by the deficiency of color vision in an individual.

Since females carry two X chromosomes, therefore color blindness will be caused only when both the X chromosomes carry gene for it as if one X chromosome carries, the female will be carrier for it.

Thus, second option is the right answer that depicts the genotype of the color blind Grandma Minion.