Question

what do a microscope, a folding piano, and the worlds biggest diamond all have in common? they were all on display at the great exhibition. this huge fair, held in london, england, in 1851, was a fair like no other, showing off items from many countries. it changed the way the shared ideas.
neighborhood
world
city

Explanation:

The text states the Great Exhibition in 1851 London showcased items from many countries, so it impacted global idea-sharing. The other options are too narrow in scope compared to the international nature of the fair.

Answer:

world