Which of the following statements regarding the transmission of infectious agents through blood transfusions is/are true? A. The transmission rates for human immunodeficiency virus (HIV) have been decreasing progressively since the early 1980s. B. The transmission rates of hepatitis have been decreasing steadily since the 1980s. C. Cytomegalovirus (CMV) is the infectious agent most commonly transmitted in blood. D. Severely immunocompromised patients (such as patients undergoing transplantation) should receive specially screened blood products.