challenge: What was the stance of the Major League Soccer's players union (MLSPU) during the conflict between the U.S. National Soccer Team Players Association and the USSF?
  
  A. They organized a separate camp with the USSF
  B. They remained neutral in the conflict
  C. They advised their membership not to accept invitations to the January camp
  D. They advised their members to accept invitations to the January camp
  Answer: 