why orc pc?

[Voadam]

Drow are given as a PC race in Unearthed Arcana. It was this book that spawned everyones favorite drow ranger.

Outside maybe the "Orcs of Thar" gazateer (assuming I am not making this up), I don't know of official rules to play an orc before 3ed--where you can play all sort of things. (and in this context, could you also play a "shadow elf", again assuming I am not making this up).

Orcs of Thar existed and allowed you to play orcs in basic D&D (I can't remeber if this was at the 2e stats as well stage). 2e also had the Complete Humanoids Handbook for playing an orc race.