The unit of permittivity of free space, \[{{\varepsilon }_{0}}\]is

• A. \[coulom{{b}^{2}}/{{(newton-metre)}^{2}}\]
• B. coulomb/newton-metre
• C. \[newton-mete{{r}^{2}}/coulom{{b}^{2}}\]
• D. \[coulom{{b}^{2}}/newton-metr{{e}^{2}}\]