What general field of medicine focuses on blood-related diseases?

Hematology is the branch of medicine that is specifically concerned with the study, diagnosis, treatment, and prevention of blood-related diseases and disorders. This field encompasses a wide array of conditions, including anemia, clotting disorders, leukemias, lymphomas, and other blood cancers. Hematologists are specialists who are trained to manage issues related to blood and the organs involved in its production, such as the bone marrow and spleen.

The other fields mentioned, while also vital areas of medicine, focus on different bodily systems and conditions. Cardiology deals with heart-related disorders, including heart disease and hypertension; endocrinology focuses on hormone-related diseases and conditions affecting the endocrine glands, such as diabetes and thyroid disorders; and nephrology is concerned with kidney health and disorders, including chronic kidney disease and kidney stones. Each of these fields has its specific area of expertise, thus underlining why hematology is the correct answer for blood-related diseases.