You are writing a method that returns an ArrayList named al. You need to ensure that changes to the ArrayList are performed in a thread-safe manner. Which code segment should you use?

You are writing a method that returns an ArrayList named al. You need to ensure that changes to
the ArrayList are performed in a thread-safe manner. Which code segment should you use?


A. ArrayList al = new ArrayList();lock (al.SyncRoot){
    return al;}
B. ArrayList al = new ArrayList();lock (al.SyncRoot.GetType()){
    return al;}
C. ArrayList al = new ArrayList();Monitor.Enter(al);Monitor.Exit(al);return al;
D. ArrayList al = new ArrayList();ArrayList sync_al = ArrayList.Synchronized(al);return sync_al;


Answer: D