In a club with 10 members, what must happen for Harry to be selected as secretary or treasurer?

For Harry to be selected as secretary or treasurer, it is essential that he must not be selected as president first because being selected for president could prevent him from being eligible for the roles of secretary or treasurer. In many clubs, the positions of president, secretary, and treasurer are typically mutually exclusive roles; thus, if Harry holds the position of president, he cannot simultaneously hold one of the other two positions. Therefore, ensuring he is not the president opens the possibility for him to take on either role, making this condition necessary for his selection as either secretary or treasurer.

The other choices suggest conditions that either limit or specify unnecessary sequences of selections, which do not address the core requirement for Harry to be eligible for the secretary or treasurer positions.