Which skin condition is characterized by increased pigmentation?

The skin condition characterized by increased pigmentation is known as chloasma. This condition, often referred to as the "mask of pregnancy," is commonly seen in women during pregnancy due to hormonal changes. It presents as brown or gray-brown patches on the skin, particularly on the face, and can also occur in other areas of the body that are exposed to sunlight. Chloasma develops because of an increase in melanin production, which leads to the noticeable darkening of the skin.

Other conditions, such as psoriasis, eczema, and rosacea, do not primarily present with increased pigmentation. Psoriasis is primarily associated with red patches covered in silvery scales, eczema manifests as patches of inflamed skin that can be itchy and may ooze, and rosacea is characterized by persistent redness and visible blood vessels, often affecting the face. These distinctions highlight chloasma's unique focus on pigmentation increases, making it the correct answer to the question regarding increased pigmentation in a skin condition.