A 5-year-old white female has multiple bruises on her lower extremities and oral mucosal bleeding of 3 days' duration. Two weeks before these signs, she had a mild respiratory tract infection. Physical examination reveals multiple ecchymoses and petechiae; no lymphadenopathy or hepatosplenomegaly is noted. The next diagnostic step is

A 5-year-old white female has multiple bruises on her lower extremities and oral mucosal bleeding of 3 days' duration. Two weeks before these signs, she had a mild respiratory tract infection. Physical examination reveals multiple ecchymoses and petechiae; no lymphadenopathy or hepatosplenomegaly is noted. The next diagnostic step is

Matching: Hemolytic anemia - Microcytosis

Matching: Anemia - Copper deficiency

Matching: Anemia - Leukemia

Matching: Red blood cell aplasia - Normal MCV