Biblical Christianity in African Perspective - O'Donovan (Question)

As you can tell by now, I am really enjoying O'Donovan's book: Biblical Christianity in African Perspective...

O'Donovan has a number of serious discussion questions at the end of chapter one.  There are no simple answers - especially when one tries really hard not to be arrogant or obnoxious (a hard one for many believers) and to frame the answer in a way that the questioner will be able to comprehend given their own world-view.  Here's the first question:

How would you answer a person...who said, "All roads lead to God since he created the world and all that is in it.  It doesn't matter which religion you follow as long as you are sincere."