When do the different levels of party organization work together most closely? a) during an election b) when they are challenged by a splinter party c) when they hold power at the same time d) after an election

The correct answer is A) during an election 

When it's election time and an official party candidate is chosen, all party members endorse the candidate and all the resources of the party are focused on electing that one candidate. It is extremely rare for members of a party to publicly oppose a chosen candidate after the candidate has been chosen by the party leadership or by the party members.