Respuesta :
Answer: The correct answer is B.
Explanation:
When the current is flowing through the vertical wire then the compass needle will points perpendicular to the wire.
When the direction of the electric current is reversed then the direction of the compass needle will also get reversed as the polarity of the magnetic field is changed.
An electric current is created in a long thin wire. When the current will increase and the direction of the current is changed then the compass will flip exactly 180 degree.
Therefore, the correct answer is B.