The degree of the differential equation $x=1+\left(\frac{d y}{d x}\right)+\frac{1}{2 !}\left(\frac{d y}{d x}\right)^2+\frac{1}{3 !}\left(\frac{d y}{d x}\right)^3+\ldots \ldots \ldots$

• A

  3
• B

  2
• Correct answer
  C

  1
• D

  not defined

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