B

Step 1: Identify the current direction in the wire and the direction of the magnetic field it produces using the right-hand rule.
Step 2: According to the configuration shown in the diagram, if the current flows horizontally to the right, then wrapping the fingers of your right hand around the wire, your thumb will point in the direction of the magnetic field lines.
Step 3: Use the right-hand rule: with the thumb pointing right (direction of current), the fingers will curl around the wire, indicating that the magnetic field is directed towards the left side of the wire.
Therefore, the magnetic field direction is towards the left.