John Is Called to the Stand and Is Sworn In Case

Multiple Choice

John is called to the stand and is sworn in.The case involves a charge of running a red light and John is the state's main witness against the defendant.When the prosecutor asks John what color the light was when the defendant went through it,John says,"I'm not sure." The prosecutor refers to John's statement at the time,where John told police that the light was red.John says that he doesn't remember giving a statement to the police.Can John be prosecuted?

A) Yes,for obstruction of justice.
B) Yes,for resisting arrest.
C) No,because his testimony does not amount to perjury.
D) No,because his testimony does not amount to witness tampering.