eV (electron volt) is the unit of

The correct answer is Option (2) → Energy

One electron volt is the energy gained by an electron when it is accelerated through a potential difference of 1 volt.

    \( \displaystyle 1\,\mathrm{eV} = (1.6\times10^{-19}\,\mathrm{C})(1\,\mathrm{V}) = 1.6\times10^{-19}\,\mathrm{J} \)

It is a charge multiplied by a potential difference, so it is a unit of energy.

Option (2) Energy — Correct. Charge times potential difference gives joules, a unit of energy.

NCERT (2026-27):
Potential Energy of a Single Charge – “… Thus, if an electron with charge q = e = 1.6 × 10^–19 C is accelerated by a potential difference of ΔV = 1 volt, it would gain energy of qΔV = 1.6 × 10^–19 J. This unit of energy is defined as 1 electron volt or 1eV, i.e., 1 eV = 1.6 × 10^–19 J.”