Directions: In this section, you will hear 3 short
passages. At the end of each passage, you will hear some questions. Both the
passage and the questions will be spoken only once. After you hear a question,
you must choose the best answer from the four choices marked [A], [B], [C] and
[D]. Then mark the corresponding letter on Answer Sheet 2 with a single line
through the centre.
Passage One Questions 26 to 28 are based on the passage you have just
heard.
A．The shortage of willing donors. B．The obtaining of moral approval. C．The complex technical procedure. D．The rejection from the immune system.