Answer:
A. a wire in a winding is broken.
Explanation:
An electric circuit can be defined as an interconnection of electrical components which creates a path for the flow of electric charge (electrons) due to a driving voltage.
Generally, an electric circuit consists of electrical components such as resistors, capacitors, battery, transistors, switches, inductors, etc.
Basically, an electric circuit is considered to be open when there's a broken continuity (broken path), which causes no current to flow through the circuit.
On the other hand, a closed circuit is one in which there's a flow of current due to a complete electrical path.
On a related note, an open winding in an electric motor means that a wire in a winding is broken.
