Speed of electrons in an electrical wire is of the order of mm per second. The light goes on immediately when we close the switch because:
A. All electrons start moving and doing work at the same time after we close the switch
B. We are using AC voltage so electrons only have to move forth and back by a very short distance.
C. Emitting light from any bulb has nothing to do with movement of electrons.
D. Electric field, which forces the electrons to start moving, propagates with speed close to the speed of light.
E. A and B are true
F. A and D are true