Let $\mathrm{y}=\frac{1}{1+\mathrm{x}+\ln \mathrm{x}}$, Then

• A

  $x \frac{d y}{d x}+y=x$
• Correct answer
  B

  $x \frac{d y}{d x}=y(y \ln x-1)$
• C

  $x^{2} \frac{d y}{d x}=y^{2}+1-x^{2}$
• D

  $x\left(\frac{d y}{d x}\right)^{2}=y-x$

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