Question: In Java, what is the effect of declaring a variable as volatile?

A) It ensures that the variable is thread-safe by allowing multiple threads to read and write to it concurrently without any additional synchronization.
B) It guarantees that changes to the variable are immediately visible to all threads, preventing cached copies from being used.
C) It makes the variable immutable, so its value cannot be changed after it is initialized.
D) It ensures that the variable's value is stored in a local cache, improving performance by reducing access time.