Under which condition can a player change their association of representation?

The correct answer is based on the rules established by FIFA regarding player representation and eligibility for national associations. A player is permitted to change their association of representation, but one specific condition is tied to the time elapsed since their last participation with the previous association. Specifically, a player must wait for at least three years after their last international match for their previous association before they can be eligible to change to a new association. This rule serves to maintain order and continuity in international football and prevents players from frequently shifting their allegiance, which could disrupt the competitive balance and the spirit of the game.

Thus, option C accurately reflects this requirement, ensuring that players have a clear and substantial break before they transition to represent another nation. The other options do not align with FIFA’s regulations, as they do not reflect the stipulations governing a player's switch in representation.