Predict the change in leukocyte count in a patient suffering from leukemia (cancer involving leukocytes)

Leukemia may be defined as the cancer of the blood cells especially white blood cells. The leukemia may occur due to mutation or may also occur due to the biological agents.

Leukemia causes the abnormal and uncontrolled growth of the blood cells. These white blood cells are unable to fight with infections and causes the bone marrow to produce impair formation of blood cells. The patient shows abnormal growth and large count of leukocytes.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.