The correct answer is D. Giemsa

Correct Answer Explanation

This is a photo depicting urticaria pigmentosa, also called maculopapular mastocytosis. It presents as reddish-brown macules and papules. Stroking of the lesions may induce urticaria like wheal (Darier’s sign).
Urticaria pigments is the most common cutaneous form of mastocytosis in children and adults. The biopsy wound stain positive for Giemsa, which stains mast cell granules.

Incorrect Answer Explanation

This is a photo depicting urticaria pigmentosa, also called maculopapular mastocytosis. It presents as reddish-brown macules and papules. Stroking of the lesions may induce urticaria like wheal (Darier’s sign).

Urticaria pigments is the most common cutaneous form of mastocytosis in children and adults. The biopsy wound stain positive for Giemsa, which stains mast cell granules.

References

Elston D, Ferringer T. Dermatopathology: Expert Consult, 2nd ed. Philadelphia: Elsevier Saunders; 2014.