I want to know the answer to the following question:
What is extensive pretrial discovery a part of?
All the background I'm provided with is that "U.S. courts pioneered the concept of the opt-out class action, by which the burden falls on class members to notify the court that they do not wish to be bound by the judgment, as opposed to opt-in class actions, where class members must join into the class.". Is that enough to answer the question?
Answer: no