In $\triangle \mathrm{ABC}$, if $a: b: c=4: 5: 6$, then $\cos \mathrm{A}: \cos \mathrm{B}: \cos \mathrm{C}=$

• Correct answer
  A

  $12: 9: 2$
• B

  $6: 5: 4$
• C

  $7: 8: 9$
• D

  $14: 11: 6$

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