The following table lists properties of three different objects.

Object A
Object B
Object C
contains copper contains rubber contains silicon
electric charges move freely electric charges do not move freely electric charges move less freely than in Object A, but more freely than in Object B

Which set of identifications is most likely correct?
a
A: conductor; B: insulator; C: semiconductor
b
A: insulator; B: semiconductor; C: conductor
c
A: semiconductor; B: conductor; C: insulator
d
A: insulator; B: conductor; C: semiconductor