题干
—
— She is a nurse.
A：What do you do?
B：What does your brother do?
C：What does your sister do?
答案(点此获取答案解析）
C
—
— She is a nurse.
A：What do you do?
B：What does your brother do?
C：What does your sister do?
可在乳酸菌作用下分解而防止“白色污染”，下列有关聚乳酸的说法正确的是( )