The equation of the common chord of the circles $x^2+y^2+2 x+3 y+1=0$ and $x^2+$ $y^2-5 x-6 y+4=0$ is

• A

  $3 x-3 y+5=0$
• B

  $7 y+9 x-3=0$
• C

  $7 x-9 y+3=0$
• Correct answer
  D

  $7 x+9 y-3=0$

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