Color blindness is reduced ability to distinguish between certain colors. This disease is caused due to_______.

The correct option is C Defective gene
Color blindness is reduced ability to distinguish between certain colors. The affected person cannot differentiate between green and red light. This disease is caused due to defective gene copies present in their DNA. Thus color blindness is an example of the genetic disorder. A genetic disorder is due to one or more abnormalities in the gene copies/genome and it could be right from birth (congenital). e.g. hemophilia, sickle cell anemia, Down's syndrome etc.