If the circles $x^2+y^2-2 \lambda x-2 y-7=0$ and $3\left(x^2+y^2\right)-8 x+29 y=0$ are orthogonal, then $\lambda=$

• A

  4
• B

  3
• C

  2
• Correct answer
  D

  1

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