Passage B
      Before you swallow that pill prescribed from your doctors, have you ever wondered what sort of testshas been done to ensure it is good for you, or is it even safe? Currently, before drugs are sold to consumers,at least four phases of premarket studies are done by researchers.
      The first study or phase one is usually an animal study if a close enough physiology is found in thatanimal to humans. The aim of giving the drug to animals is to protect the lives of humans as it is moreethically correct to save valuable human lives rather than prevent animal fatalities.
     The next three phases include three clinical studies and only proceeds once the first phase is passed. Inphase two, the most initial test on people is done on very few healthy volunteers to check that there are nosevere side effects. Phase three is also known as an efficacy study (a study to see if there are any benefitsand/or side effects) and is done on patients with disease. This number, however, is still kept very small –about 200 to 500 volunteers – to save resources and not waste volunteers’ time if the drug is not effective intreating their diseases.
      Phase four includes extensive clinical trials on a greater number of patients (still volunteers) so thatresearchers can deduce that the drug actually works for all patients by ruling out random error.
      Upon the completion of the above four phases, the drug is allowed to be sold and should be safe forwidespread use.
36. According to the article, why are drugs tested on animals?
(A) Because animals are prone to mutation.
(B) Because animal testing is to save human lives.
(C) Because animals are more likely to show side effects.
(D) Because buying animals is more prodigal than buying humans.