Man...poorly constructed question! We only have to prove 'it' if Germans ARE the tallest people in the world. Therefore, if we are forced to prove it, it must be the case that Germans are actually the tallest people!

We could also randomly sample heights from people considered German and compare it to a random sampling of heights from people in non-German groups we are interested in. Assuming we have resources to get large enough samples and can account for a variety of biases, some ANOVA and other stats stuff can get us the answer.

I first asked how would we define germans. People who were born in germany. People who lived in Germany. From East or West. The food they ate (had to do likely w/ $) and stuff like that.