The word parts "Hemat/o" and "-emia" both relate to the concept of blood. "Hemat/o" specifically refers to blood, while "-emia" indicates a condition or presence of a substance in the blood. Therefore, when combined, "Hemat/o" and "-emia" create the term "hematemia," which means the presence of blood in the urine. In this case, the correct answer is "blood" because it accurately represents the meaning of the word parts.