$A$ plano-convex lens is placed with its curved surface on a plane glass plate,creating a thin air film. With monochromatic light,this thin film produces an interference pattern due to reflections from the top curved surface and the bottom glass plate surface.
Statement-$1$: When light is reflected from the air-glass plate interface,it undergoes a phase change of $\pi$.
Statement-$2$: The center of the interference pattern is dark.

• A
  Statement-$1$ is true,Statement-$2$ is true,and Statement-$2$ is not the correct explanation of Statement-$1$.
• B
  Statement-$1$ is false,Statement-$2$ is true.
• C
  Statement-$1$ is true,Statement-$2$ is false.
• D
  Statement-$1$ is true,Statement-$2$ is true,and Statement-$2$ is the correct explanation of Statement-$1$.