Which of the following areas is most commonly affected by psoriasis?

Explanation: Psoriasis is believed to have a genetic component, and it is considered an autoimmune disorder where the immune system mistakenly attacks healthy skin cells, leading to the characteristic skin changes.

Incorrect choices: a. Poor hygiene and lack of skin care - Psoriasis is not caused by poor hygiene or lack of skin care.

b. Exposure to environmental toxins - While environmental factors may trigger or worsen psoriasis in some individuals, they are not the primary cause of the condition.

d. Excessive sun exposure - Sun exposure may improve psoriasis symptoms in some people, but it is not the underlying cause of the condition.

Explanation: Psoriasis is characterized by the presence of itchy, raised, red patches on the skin with silvery scales. These patches are known as plaques and are a hallmark feature of psoriasis.

Incorrect choices: a. Painful, deep ulcers on the skin: This description does not align with psoriasis. Psoriasis plaques are not typically painful or ulcerated.

c. Small, fluid-filled blisters on the palms and soles: This description is more characteristic of a condition called palmoplantar pustulosis, not psoriasis.

d. Thickened, hardened skin with deep cracks: This description is more typical of a condition called lichenified eczema or chronic contact dermatitis, not psoriasis.