I am new to react. I write a script to loop UK json file(../data/UK.json) to show cities on screen. Inside UK.json, it’s a list of city information in UK.

Such as :
[“Avon”,
“Bedfordshire”
…
…
“Tyrone”
]

The code will loop this UK json file and show each city in the screen.
Now I want to add a param to let people choose which country to show. I add another 4 json file,