If e is the electronic charge, $c$ is the speed of light in free space and $h$ is Planck's constant, the quantity $\frac{1}{4 \pi \varepsilon_{0}} \frac{| e |^{2}}{h c}$ has dimensions of .......
  • A$\left[ M ^{0} L ^{0} T ^{0}\right]$
  • B$\left[ L C ^{-1}\right]$
  • C$\left[ M L T ^{-1}\right]$
  • D$\left[ M L T ^{0}\right]$
JEE MAIN 2021, Diffcult
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