Question: What is the purpose of the volatile keyword in Java?

A) It indicates that a variable's value will be modified by different threads and ensures visibility of changes to all threads.
B) It marks a variable as immutable, preventing any modification after it is initialized.
C) It indicates that a variable is local to a method and should not be accessed from outside that method.
D) It allows a variable to be serialized automatically when an object is written to a stream.