The correct order of atomic radii in group $13$ elements is

• Correct answer
  A

  $\mathrm{B}<\mathrm{Ga}<\mathrm{Al}<\mathrm{Tl}<\mathrm{In}$
• B

  $\mathrm{B}<\mathrm{Al}<\mathrm{Ga}<\mathrm{In}<\mathrm{Tl}$
• C

  $\mathrm{B}<\mathrm{Al}<\mathrm{In}<\mathrm{Ga}<\mathrm{Tl}$
• D

  $\mathrm{B}<\mathrm{Ga}<\mathrm{Al}<\mathrm{In}<\mathrm{Tl}$

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