You are answering a USMLE-style medical question. Question: A 6-month-old boy presents to a pediatrician for the evaluation of recurrent bacterial infections. He has a history of a variety of bacterial infections since birth. Physical examination reveals light-colored skin with silver-colored hair. The pediatrician suspects an immunodeficiency disorder and decides to order several tests. Study of the boy’s neutrophils reveals that they contain large cytoplasmic vacuoles. Genetic studies show a mutation in the LYST gene. Which of the following is the most likely diagnosis in this patient? Options: A) Acquired immunodeficiency syndrome (AIDS) B) Common variable immunodeficiency C) Chediak-Higashi syndrome D) Leukocyte adhesion deficiency–1 Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.