Today’s topic is blood. Blood is indeed in the news, for on the __(1)__ of that announcement comes a report of tests __(2)__ in the United States and Japan __(3)__ artificial blood. After an accident, time is crucial for a person suffering from extensive blood loss, and transfusion of real blood must often __(4)__ a time-consuming test for blood type. Plasma does not require such a test but, because it can carry little oxygen, it is not a wholly satisfactory substitute. Perfluorocarbons appear to offer an answer. They are utilized in combination with an emulsion called Fluosol-DA, which provides a number of additional advantages __(5)__ real blood. These include the absence of a need for blood tests, the fact that it can be frozen for as long as two years, its elimination eventually as a gas through the lungs, and the impossibility of its transmitting such problems as hepatitis. 【題組】1. (A) feet (B) heels (C) legs (D) steps