Pigmentation resulting from infrared radiation is

• A. Homogenous
• B. Heterogenous
• C. Mottled
• D. Dark red, spotted, or forms a network

Answer: (C)

Infrared radiation heats the skin unevenly, causing pigment changes to appear in irregular, blotchy patches rather than as a uniform change. This patchwork, or mottled, pattern reflects the different responses of skin cells in adjacent areas to the heat. If the pigmentation were homogeneous, the whole area would change in the same way, which infrared exposure typically does not produce. Patterns described as dark red, spotted, or forming a network suggest vascular changes rather than pigment distribution, and a vague heterogeneous appearance doesn’t capture the characteristic blotchy look infrared-induced pigmentation often shows. So the mottled appearance best matches how infrared radiation affects pigmentation.