i pick up this question from past paper on June 2005, Paper 1, No35. here is the question:
Some antibiotics are used in animal feed to reduce disease. what explains why these antibiotics should not be used in the treatment of human disease?
A.Humans may be allergic to these antibiotics
B.Human cells may stop responding to these antibiotics
C.pathogenic bacteria may develop resistance to these antibiotics
D.Useful gut bacteria may be killed by these antibiotics
according to the choices given, the answers are quite similar. What is the best way to choose the answer, and why the best answer is C?
B is incorrect - antibiotics are aimed at bacterial cells, not human cells. A and D may be true but there is no evidence for it and these could be true of ANY antibiotic. C is therefore the only answer left.