I think you should choose an exciting topic, something maybe related to what's trending or being debated about, etc. Like gender equality, gobal issues (as said by the person before me) or perhaps it can be about your own personal life. I know I'm going to present a speech about my grandmother because of what an inspiring person she was, so it doesn't necessarily have to be about global issues.
In Jack London's "To build a fire" the main theme is Man vs. Nature, the main character is crossing the Alaskan frozen landscape, following the path of the Yukon river. He dismisses the advice of the old-timer and he also doesn't pay attention to his companion, the dog who can feel the threat of the harsh weather. The right answer is the second option.
