If a circle $S$ passes through the origin and makes an intercept of length 4 units on the line $x=2$, then the equation of the curve on which the centre of $S$ lies is

• A

  $y^2-4 x=8$
• Correct answer
  B

  $y^2+4 x=8$
• C

  $x^2+4 y=8$
• D

  $x^2-4 y=8$

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