In Regards to the Timing of Prosecution's Pretrial Disclosure of Evidence

In regards to the timing of prosecution's pretrial disclosure of evidence to the defense ______.

A) courts are in agreement as to the timing as there are precise standards
B) courts are not in agreement as to the timing because the standards lack precision
C) courts require a hearing before disclosure can be made
D) courts have stated that judges must determine individually when disclosure must occur,and that date needs to be set prior to each trial