A Nurse Is Providing Care for a 17-Year-Old Boy Who

A nurse is providing care for a 17-year-old boy who has experienced recurrent sinus and chest infections throughout his life and presently has enlarged tonsils and lymph nodes. Blood work indicated normal levels of B cells and free immunoglobulins but a lack of differentiation into normal plasma cells. The boy is currently receiving intravenous immunoglobulin (IVIG) therapy. What is the boy's most likely diagnosis?

A) X-linked hypogammaglobulinemia
B) Transient hypoglobulinemia
C) Common variable immunodeficiency
D) IgG subclass deficiency