Which One of the Following Statements Is CORRECT

Which one of the following statements is CORRECT?

A) The Supreme Court has ruled that witnesses appearing before a grand jury have the right to be represented by counsel before the grand jury.
B) Rules of evidence are applied before a grand jury on the same basis as in a criminal trial.
C) Most states have now adopted liberal rules allowing pretrial discovery in criminal cases.
D) A defendant who chooses self-representation has a constitutional right to receive instructions from the presiding judge on courtroom procedures.