题干
People have lots of problems living in the central Australian desert, ____ the lack of water is the most serious one.
A：of which
B：which
C：for which
D：where
答案(点此获取答案解析）
A
，下列有关乳酸的说法不正确的是（ ）
”表示抗生素：“ 
”示被消灭的细菌