Topic for speech

I am undecided between 1 of 3 of the topics, they are:

1) The greatest challenge of the healthcare industry today & why?

2)If the world could sustain more people, would I agree or disagree?

3) Experimenting on animals is necessary & justifiable, Would I agree or disagree?

After I do a little research, I will make a dicision which one I will write about.

* I have decides to do it on Experimenting on animals