The correct statement regarding ethane conformation is :

Rotation around carbon-carbon bond in ethane molecule is not possible, because ethane molecule contains both sigma $\left(\sigma \right)$ bond and pi $\left(\pi \right)$ bond between the carbon and carbon and ethane has very high boiling point.

Rotation around carbon-carbon bond in ethane molecule is not possible, because ethane molecule contains a pi $\left(\pi \right)$ bond between the carbon and carbon and ethane has very low melting point.

Rotation around carbon-carbon bond in ethane molecule is possible because of cylindrical symmetry of sigma $\left(\sigma \right)$ bond between carbon-carbon atoms.

Rotation around carbon-carbon bond in ethane molecule is not possible, because ethane molecule contains both sigma $\left(\sigma \right)$ bond and pi $\left(\pi \right)$ bond between the carbon and carbon.