Use "at" for addresses, "on" for streets, and "in" for inside of a building, neighborhood, city, country, etc. Examples: "The restaurant is at 200 Center Road" = The restaurant's address is 200 Center Road "The restaurant is on Center Road" = The restaurant is on a street named Center Road "The restaurant is in Westfield Mall on Center Road" = The restaurant is located inside of a bigger structure, and that building is on a street named Center Road "The restaurant is in Westfield Mall at 200 Center Road" = The restaurant is located inside of a bigger building, and that building's address is 200 Center Road "The restaurant is in London, on Center Road" = The restaurant is in the city of London, and within London is on a street named Center Road

Always use "at" when you're giving a specific address. When you're just giving the street, use "on" in American English or "in" in British English.

I consider all to be correct. IN makes good sense because the restaurant is IN that building. ON makes less sense than the others but is nonetheless acceptable because the restaurant is ON Center Road. It would be better to say "The restaurant is ON Center Road AT 200". AT makes sense because "200 Center Road" is where the restaurant is located. When you use the preposition "at", it is like pointing AT the restaurant's location.

The correct preposition to use with an address is "at": * The restaurant is at 200 Center Road. "At" is used for specific locations or addresses. If you were referring to just the street without a specific address, you'd use "on": * The restaurant is on Center Road. "On" is for streets, and "in" is generally used for larger areas like cities or neighborhoods, not specific addresses.

The restaurant is in the mall. The restaurant is on 4th street. The restaurant is at 200 North Center Road.