I too had to look it up - Stongs likewise has it translated variously as who, which or what.
The Strongs reference even give the number of times it is variously tranlated in both the KJV and the NAS as follows:
KJV (537) - misc, 67; what, 260; which, 17; who, 102; whom, 25; why, 66;
NAS (225) - anything, 1; how, 2; person, 1; something, 3; suppose one, 2; what, 5; what each, 1; which, 24; which one, 3; who, 128; whom, 16; whose, 6; why, 33;
Peace
James