Question ID:PT57 S3 Q11 Passage:Many vaccines create immunity to viral diseases by introducing a certain portion of the disease-causing virus's outer coating into the body.  Exposure to that part of a virus is as effective as exposure to the whole virus in stimulating production of antibodies that will subsequently recognize and kill the whole virus.  To create a successful vaccine of this type, doctors must first isolate in the disease-causing virus a portion that stimulates antibody production.  Now that a suitable portion of the virus that causes hepatitis E has been isolated, doctors claim they can produce a vaccine that will produce permanent immunity to that disease. Stem:Which one of the following, if true, most strongly counters the doctors' claim? Correct Answer Choice:AChoice A:Most of the people who contract hepatitis E are young adults who were probably exposed to the virus in childhood also. Choice B:Some laboratory animals exposed to one strain of the hepatitis virus developed immunity to all strains of the virus. Choice C:Researchers developed a successful vaccine for another strain of hepatitis, hepatitis B, after first isolating the virus that causes it. Choice D:The virus that causes hepatitis E is very common in some areas, so the number of people exposed to that virus is likely to be quite high in those areas. Choice E:Many children who are exposed to viruses that cause childhood diseases such as chicken pox never develop those diseases.