ANSWER
C. a current-carrying wire makes a compass needle move
EXPLANATION
The connection between electricity and magnetism is observed when both a magnetic and an electric field are created.
A current-carrying wire creates an electromagnetic field around it - i.e. it creates both types of fields mentioned above. Because it creates a magnetic field, it will make a compass needle move since a compass works with a magnetic field - usually Earth's magnetic field.
Hence, of these options, "a current-carrying wire makes a compass needle move" shows the connection between electricity and magnetism.
