Objects are not collected if they are accessible from live threads.
[C].
An OutOfMemory error is only thrown if a single block of memory cannot be found that is large enough for a particular requirement.
[D].
Objects that have finalize() methods always have their finalize() methods called before the program ends.
Answer: Option B
Explanation:
Option B is correct. If an object can be accessed from a live thread, it can't be garbage collected.
Option A is wrong. Runtime.gc() asks the garbage collector to run, but the garbage collector never makes any guarantees about when it will run or what unreachable objects it will free from memory.
Option C is wrong. The garbage collector runs immediately the system is out of memory before an OutOfMemoryException is thrown by the JVM.
Option D is wrong. If this were the case then the garbage collector would actively hang onto objects until a program finishes - this goes against the purpose of the garbage collector.
