The pair of molecules / ions with the same bond order value is

• A

  $\mathrm{B}_2, \mathrm{C}_2$
• Correct answer
  B

  $\mathrm{O}_2, \mathrm{C}_2$
• C

  $\mathrm{O}_2^{+}, \mathrm{O}_2^{-}$
• D

  $\mathrm{H}_2^{+}, \mathrm{Li}_2$

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