Question: In a 29-year-old woman the following parameters are in the course of a routine analysis: Hb 11.5 g / dL, VCM 70 fl, HCM 28 pg, Ferritin 10 ng / mL, leukocytes 5,200 / mm3, platelets 335,000 / mm3. Physical examination is normal. The most indicated exploration in this situation is: 
 Options:  <1> Gynecological exploration. <2> Study of occult blood in stool. <3> Radiological study of the digestive system. <4> Electrophoresis of hemoglobins. <5> Test of Coombs.
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