_____ is due to the lack of functioning cones.

• A. Monochrome color blindness
• B. Deuteranopia
• C. Protanopia
• D. Tritanopia

Answer: (A)

Verified step by step guidance

1. Begin by understanding the role of cones in the human eye. Cones are photoreceptor cells responsible for color vision. They are sensitive to different wavelengths of light, allowing us to perceive a range of colors.
2. Recognize that color blindness occurs when one or more types of cones are not functioning properly. This can lead to difficulty in distinguishing certain colors.
3. Identify the types of color blindness: Monochrome color blindness, Deuteranopia, Protanopia, and Tritanopia. Each type is associated with the dysfunction of specific cones.
4. Monochrome color blindness is due to the lack of functioning cones altogether, resulting in the inability to perceive any color, only shades of gray.
5. Deuteranopia, Protanopia, and Tritanopia are specific types of color blindness related to the dysfunction of green, red, and blue cones respectively. Understand that these conditions affect the perception of specific colors rather than all colors.