I believe the rule is the country that is your main destination of the first trip you'll take on the visa. So, if you are making only one trip and visiting primarily that country, then you'd apply to that country. If you are going to make multiple trips on the same visa (i.e. return to India in between), then you'd visit the country that you are visiting on the first trip. If you are visiting several countries equally, you have some wiggle room.