question: Q:A 41-year-old man comes to the physician for generalized fatigue and weakness of his left hand for 4 weeks. During this period he also had multiple episodes of cramping abdominal pain and nausea. He works at a battery manufacturing plant. His temperature is 37°C (98.6°F), pulse is 75/min, and blood pressure is 124/74 mm Hg. Examination shows pale conjunctivae and gingival hyperpigmentation. There is weakness when extending the left wrist against resistance. The brachioradialis reflex is 1+ on the left and 2+ on the right. The radial pulse is palpable bilaterally. The remainder of the examination shows no abnormalities. Further evaluation of this patient is most likely to show which of the following?? 
  {'A': 'Basophilic stippling of erythrocytes', 'B': 'Beta‑2 microglobulin in urine', 'C': 'White bands across the nails', 'D': 'Increased total iron binding capacity', 'E': 'Septal thickening on chest x-ray'},