C++

If you want to ensure that the object you are accessing can't be changed, which of the following options can you use? O Option 1: Top-level const pointer O Option 2: Low-level const pointer Option 3: Const reference Both options 1 and 2 Both options 2 and 3 Both options 1 and 3 All of options 1, 2, and 3 None of the above can make that guarantee