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: With what scope is the Theory of the Melzack Gate and Wall related ?: 
 Options:  <1> Cancer. <2> HIV infection <3> Renal problems. <4> Pain. <5> Cardiovascular disorders

A: 4
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Q: Question: The Merkel cells are: 
 Options:  <1> Secretors of neuropeptides and sensory. <2> Secretors of mucus. <3> Migratory <4> From Schwann. <5> Fibroblasts.

A: 1
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Q: Question: Immediate hypersensitivity reactions or allergy are mediated by: 
 Options:  <1> Autoantibodies <2> Antigen-antibody complexes. <3> IgE <4> Th1 lymphocytes. <5> Th17 lymphocytes.

A:
3
****