Final answer:
A goalkeeper can be designated as a Captain or Alternate Captain, as the role relies on leadership qualities rather than a specific field position.
Step-by-step explanation:
In the context of lacrosse and other team sports, there are rules regarding who can hold leadership positions like captains. Generally speaking, a goalkeeper can indeed be designated as a Captain or an Alternate Captain. This is because the captaincy role is typically about leadership and representing the team during discussions with referees, rather than being tied to a specific position. Team dynamics and the qualities of the individual player usually determine who is chosen as a captain, not their position on the field or court.