听下面一段材料，回答第1-3题。 1. What is the main topic of the talk? A. S

来源：学生作业帮编辑：神马作文网作业帮分类：英语作业时间：2024/10/13 16:20:46

听下面一段材料，回答第1-3题。

1. What is the main topic of the talk?

A. Substances used in bone repair.
B. How to maintain healthy bones.
C. The structure of sea coral.

1. What does the speaker mention as a disadvantage of transplanting bone from donors?

A. It is too expensive.
B. The patient might reject the bone.
C. There are not enough donors.

3. What is one reason that coral works well as a replacement for bone?

A. It has holes into which new bone material can grow.
B. Its composition is similar to that of bone.
C. It is not as brittle as bone.

1-3: ABA

请听下面一段材料,回请听下面一段材料,回答第1至3题. 1.What is the total number of s 听下面一段材料，回答第1-3题。 1. What is the speaker doing? A. Giving a s 听下面一段材料，回答第1～3题。 1. What is the speaker doing? A. Giving a s 听下面一段材料，回答第1-4题。 1. What is the aim of the program? A. To ke 听下面一段材料，回答第1至4题。 1. What is the aim of the program? A. 请听下面一段材料,回请听下面一段材料,回答第1至3题. 1.What is the purpose of the wo 听下面一段材料,回答听下面一段材料,回答第1至3题. 1.What is the man? A.A businessm 听下面一段材料,回答第1至第3题. 1. What is the phone number of Greg Hunter 听下面一段材料，回答第1至3题。 1. What is the most probable occupation of 听下面一段材料，回答第1-3题。 1. What is the most probable occupation of 听下面一段材料，回答第1-3题。 1. What does the woman buy? A. A pair of sh 听下面一段材料，回答第1-3题。 1. When is the man’s daughter’s birthday? A