The quantities $x = \frac{1}{\sqrt{\mu_{0} \varepsilon_{0}}}$,$y = \frac{E}{B}$,and $z = \frac{l}{CR}$ are defined,where $C$ is capacitance,$R$ is resistance,$l$ is length,$E$ is electric field,$B$ is magnetic field,and $\varepsilon_{0}, \mu_{0}$ are free space permittivity and permeability respectively. Then:

• A
  Only $x$ and $y$ have the same dimension
• B
  $x, y$ and $z$ have the same dimension
• C
  Only $x$ and $z$ have the same dimension
• D
  Only $y$ and $z$ have the same dimension