Question

According the the arrhenius theory, which species does an acid produce in an aqueous solution?

Answer 1

Note: Above question is incomplete: Complete question is read as 
According the the arrhenius theory, which species does an acid produce in an aqueous solution?
A) hydrogen ions B) hydroxyl ions C) Sodium ions D) Chloride ion
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Correct answer for above question is A) Hydrogen ions

Reason:
According the Arrhenius theory of acid and base, acid generates hydrogen ions in aqueous medium, while bases generates hydroxyl ions in aqueous medium.  
Example of Acid:
HCl(aq)          →          H+(aq)    + Cl-(aq)

Example of Base:
NaOH(aq)           →          Na+(aq)       +     OH-(aq)