Which of the following pair does not have similar dimensions

Dimensional formula for volume elasticity is

Give an example of
$(a)$ a physical quantity which has a unit but no dimensions
$(b)$ a physical quantity which has neither unit nor dimensions
$(c)$ a constant which has a unit
$(d)$ a constant which has no unit

Dimensional formula for torque is

The dimensions of ${e^2}/4\pi {\varepsilon _0}hc$, where $e,\,{\varepsilon _0},\,h$ and $c$ are electronic charge, electric permittivity, Planck’s constant and velocity of light in vacuum respectively

The dimensions of resistivity in terms of $M,\,L,\,T$ and $Q$ where $Q$ stands for the dimensions of charge, is