Question

Which of the following word groups are:(1)fragment,(2)fused sentence,(3)comma splice,(4)correct sentence.
a) Writing for days on my report.I completed it today.
b) As the rotor revolves toward position 3,fewer and fewer lines of force pass through the station coil.
c) Excessive current can cause a conductor to melt or break this happens commonly in ignition wires when they carry more voltage than they are designed to carry.
d) Mr. and Mrs.Randall,who are friends of the family.