D i.e. Triamcinolone cream topical applicationRef: Rook's Textbook of Dermatology, 8th edition, page 24.20Explanation:The given history of erythematous scaly papules with crusting over antecubital fossa in a boy is suggestive of a diagnosis of atopic dermatitis. The fact that he was advised emollient in shower also suggests the same as dry skin is quite common in patients with atopic dermatitis.The treatment of choice for limited atopic dermatitis is topical corticosteroids. In the given option Triamcinolone cream is the only topical corticosteroid hence that option is right. This will decrease the inflammation and decrease the lesions.Atopic dermatitis shows typical distribution according to the age. In the infants it frequently involves the face and the extensors. In the childhood phase and adults flexural involvement is very common.