In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.

Q: Question: Observe that the liquids coming from the synthesis of chloroquine had an antibacterial activity gave rise to the discovery of the quinolones. This group of antibiotics has various characteristics such as: 
 Options:  <1> Fluoroquinolones have a smaller spectrum of activity than first-generation quinolones. <2> The second generation quinolones are very effective against anaerobes. <3> Fluoroquinolones are not effective against enterobacteria. <4> Fluoroquinolones are effective against Gram-positive but less than Gram-negative. <5> The third and fourth generation fluoroquinolones are not effective against streptococci or staphylococci.

A: 4
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Q: Question: We want to study if Vitamin D can increase the incidence of breast cancer. In our area we have a population registry of cancer. To achieve our goal, all women diagnosed with breast cancer are selected from the register we have and each case pairs with two controls. What study design has been chosen? 
 Options:  <1> Prospective cohort study. <2> Cases and controls study. <3> Case-control study nested. <4> Retrospective cohort study. <5> Ecological study

A: 3
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Q: Question: A 45-year-old patient with a moderate smoking habit, no drinker, no other history of interest who has been diagnosed with squamous carcinoma of the oropharynx cT1N2b. It is pending decision of treatment in committee. What infectious agent would you be interested in confusing before proposing the treatment? 
 Options:  <1> Helicobacter pylori. <2> Herpes Simplex virus type 2. <3> Human papilloma virus. <4> Epstein Barr virus. <5> Cytomegalovirus.

A:
3
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