Consider three quantities $x = E/B$,$y = \sqrt{1/(\mu_0 \varepsilon_0)}$ and $z = l/RC$. Here,$l$ is the length of a wire,$C$ is capacitance,and $R$ is resistance. All other symbols have standard meanings. Which of the following statements is correct?

• A
  $x$ and $y$ have the same dimensions.
• B
  $y$ and $z$ have the same dimensions.
• C
  $z$ and $x$ have the same dimensions.
• D
  All of the above.