The correct answer is A. A fuse is connected in series with a circuit. This means that the fuse is connected directly between the power source and the load. If there is a problem with the circuit, such as a short circuit, the fuse will blow and break the circuit, preventing damage to the circuit or the load.
Option B is incorrect. A fuse is not connected in parallel with a circuit. If a fuse were connected in parallel, it would not be able to protect the circuit from a short circuit.
Option C is incorrect. A fuse is not connected either in series or in parallel with a circuit. A fuse is always connected in series with a circuit.
Option D is incorrect. A fuse is connected in series with a circuit.