Step 1: Formula of electric flux.
Electric flux is defined as:
\[
\phi = \vec{E} \cdot \vec{A}
\]
where $\vec{E}$ is electric field (unit: Volt/m) and $\vec{A}$ is area ($m^2$).
Step 2: Unit calculation.
So, unit = (Volt/m) $\times$ ($m^2$) = Volt $\times$ metre.
Step 3: Conclusion.
Thus, the correct answer is Volt $\times$ metre.