下列属于显影液的主要成分的是
A. 氯化银
B. 对苯二酚
C. 碳酸钠
D. 氯化钠
E. 氢氧化钾
肢端肥大症患者应摄取的最佳体位是
A. 双手正位
B. 双足正位
C. 头颅正位
D. 蝶鞍侧位
E. 双膝正位
When the author says that "the results of the protests and other tactics have been mixed" (in Para. 3), he means the protest and other tactics ______.
A. have produced desired effects
B. almost amounted to nothing
C. have some influence on the public
D. have proved to be too radical
What does the passage mainly discuss
A. How parasites reproduce.
B. How organisms react to invaders.
C. How antibiotics work to cure disease.
D. How the immune system of vertebrates developed.
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