When hovering on countries, they will all be selected, while when click a specific country, then there will be only one country being selected.

I actually don't tackle the task. I have tried the method in Bowl of Fruit - Click to Select (https://vizhub.com/NTCHANG1289/17953e2e1e864c4e8ab5a637553dec49), but I didn't successfully get any result from the map.

The method I used in this one is found on the website Making a map using D3.js

But I am not really sure: is such method more like the cheap tricks example?

I would say this is the most difficult assignment as to now~~~