A: Who has the best soccer team?
B: I think Brazil does.

Vedi una traduzione

"which" can only be used to choose from a group. You can say "which country has the best soccer team". In this example "countries" are the group you are choosing from.

If in the conversation you have already mentioned the group, then "which" is fine.
person 1: Every school has a soccer team.
Person 2: which has the best team?
In this example the group you are choosing from was already mentioned, schools.

If the group has not been mentioned then you can't use which. You can use "who" but it does not specify the group you are choosing from, you have to guess.
Person 1: Who has the best soccer team?
Person 2: Brazil
or
Person 2: the school in the city
or
Person 2: the players in the red shirts