Question regarding thread safety

static void Main()
    {
        var foo = new Foo();
        foo.instanceA = new Bar();
        foo.instanceB = new Bar();
        
        //Assuming every method on Bar is thread safe is it safe to access the foo object to call a method on Bar from any thread?
                foo.instanceA.DoSomething();
                
        
    }
    public class Foo
    {
        public Bar instanceA;
        public Bar instanceB;
    }
    
    public class Bar
    {
        public void DoSomething()
        {
            
        }
    }