Answer: Option (a) is the strong acid.
Step-by-step explanation:
Hydrochloric acid is a strong acid and when it is added to water then the following reaction takes place.
![HCl + H_(2)O \rightarrow H_(3)O^(+) + Cl^(-)](https://img.qammunity.org/2019/formulas/chemistry/high-school/blctzm184qqnv9jkpe8jf2h1kv371mxuq6.png)
where,
is a conjugate acid and
is a conjugate base.
Therefore, when we add HCl into water then it dissociates completely into hydronium ion and chlorine ion.
Thus, we can conclude that a strong acid is disassociated completely, producing more conjugate base.