Please give an explanation on the answer that was picked. Thank You. A mother brings her 20-month-old son to the pediatrician. She suspects that he has a sinus infection. During the visit, the mother voices her concern that her son has been having frequent infections since he was around 6 months old. She states that he recovers only briefly before he has another ear infection, sinus infection, or even pneumonia. The pediatrician reviews the chart and acknowledges to the mother that her son has had more infections than the average child. 1. The pediatrician orders laboratory analysis targeted at an immunodeficiency diagnosis. Which of the following tests would be most beneficial in diagnosing this patient? A). Red blood cell count B). Immunoglobulin levels C). Metabolic panel D). Gram stain and culture 2. The child’s IgG, IgM, and IgA levels are very low, indicating a lack of immunoglobulins. Taking into account the child's age and sex, which primary immunodeficiency is most likely? A). X-linked Bruton’s tyrosine kinase deficiency (Btk) B). Common variable immune deficiency (CVI) C). IgG subclass deficiency D). Wiskott-Aldrich syndrome (WAS)

Please give an explanation on the answer that was picked. Thank You. A mother brings her 20-month-old son to the pediatrician. She suspects that he has a sinus infection. During the visit, the mother voices her concern that her son has been having frequent infections since he was around 6 months old. She states that he recovers only briefly before he has another ear infection, sinus infection, or even pneumonia. The pediatrician reviews the chart and acknowledges to the mother that her son has had more infections than the average child. 1. The pediatrician orders laboratory analysis targeted at an immunodeficiency diagnosis. Which of the following tests would be most beneficial in diagnosing this patient? A). Red blood cell count B). Immunoglobulin levels C). Metabolic panel D). Gram stain and culture 2. The child’s IgG, IgM, and IgA levels are very low, indicating a lack of immunoglobulins. Taking into account the child's age and sex, which primary immunodeficiency is most likely? A). X-linked Bruton’s tyrosine kinase deficiency (Btk) B). Common variable immune deficiency (CVI) C). IgG subclass deficiency D). Wiskott-Aldrich syndrome (WAS)