The Spanish flu of 1918 was caused by an ________ influenza virus.

The Spanish flu of 1918 was caused by an ________ influenza virus.
 
  A) H2N1
  B) H5N1
  C) H1N1
  D) H2N2

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Which of the following statements about chlamydial infections is TRUE?
 
  A) Chlamydial diseases are not reportable diseases.
  B) Chlamydial diseases are less prevalent than gonorrhea.
  C) Chlamydial diseases can lead to acute complications.
  D) All of the statements are true.

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Which of the following is a cure for mumps?
 
  A) a vaccine
  B) an antibiotic
  C) host antibodies
  D) an antiviral

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Once a person has been infected with Neisseria gonorrhoeae, the individual
 
  A) acquires transient immunity, which prevents subsequent infection for about a year.
  B) acquires no immunity, and thus could be reinfected immediately.
  C) requires immunization by a vaccine.
  D) requires immunization by an antiserum.

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Encapsulated strains of Streptococcus pneumoniae are particularly pathogenic, because they
 
  A) produce exotoxin A.
  B) produce exotoxin B.
  C) are potentially very invasive.
  D) produce M protein surface antigens.