'N' point charges are distributed into two groups and separated by a fixed distance. Then the ratio of maximum to minimum forces between the two groups is $(\mathrm{N}$ is even and greater than 2). Options :

• A

  $\frac{(\mathrm{N}-1)^2}{4 \mathrm{~N}^2}$
• B

  $\frac{4 \mathrm{~N}^2}{\mathrm{~N}-1}$
• Correct answer
  C

  $\frac{\mathrm{N}^2}{4(\mathrm{~N}-1)}$
• D

  $\frac{2 \mathrm{~N}^2}{\mathrm{~N}-1}$

Hence, the correct answer is option: 'C'.