question: Q:A 46-day-old baby is admitted to the pediatric ward with an elevated temperature, erosive periumbilical lesion, clear discharge from the umbilicus, and failure to thrive. She is the first child of a consanguineous couple born vaginally at 38 weeks gestation in an uncomplicated pregnancy. She was discharged home from the nursery within the first week of life without signs of infection or jaundice. The umbilical cord separated at 1 month of age with an increase in temperature and periumbilical inflammation that her mother treated with an herbal decoction. The vital signs are blood pressure 70/45 mm Hg, heart rate 129/min, respiratory rate 26/min, and temperature, 38.9°C (102.0°F). The baby's weight is between the 10th and 5th percentiles and her length is between the 50th and 75th percentiles for her age. The physical examination shows an erosive lesion with perifocal erythema in the periumbilical region with drainage but no pus. The rest of the examination is within normal limits for the patient’s age. The complete blood count shows the following results:
  Erythrocytes 3.4 x 106/mm3
  Hb 11 g/dL
  Total leukocyte count
  Neutrophils
  Lymphocyte
  Eosinophils
  Monocytes
  Basophils 49.200/mm3
  61%
  33%
  2%
  2%
  2%
  Platelet count 229,000/mm3
  The umbilical discharge culture shows the growth of Staphylococcus aureus. Flow cytometry is performed for suspected primary immunodeficiency. The patient is shown to be CD18-deficient. Which of the following statements best describes the patient’s condition?? 
  {'A': 'The patient’s neutrophils fail to produce reactive oxygen species to destroy engulfed bacteria.', 'B': 'The patient’s leukocytes cannot interact with selectins expressed on the surface of endothelial cells.', 'C': 'The patient’s leukocytes fail to adhere to the endothelium during their migration to the site of infection.', 'D': 'There is excessive secretion of IL-2 in this patient.', 'E': 'The patient has impaired formation of membrane attack complex.'},