Select the ion.
hcl
h2o
h3o+1

Answer : The correct option is,

Explanation :

Ion : It is formed by the loss or gain of one or more electrons. It is an electrically charged atom or group of atoms.

Positive charged ion is formed by the loss of electrons and is known as cation and negative charged ion is formed by the gain of electrons and known as anion.

From the given options,

and are the neutral molecules. while the is a positive ion species that is cation because it has (+1) charge.

Hence, the correct option is,

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