The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
Answer is A.
A material body is ultimately composed by elementary particles like electrons, protons and neutrons, many of which have an electric charge. A body may be called 'electrically neutral' when adding the electric charges, some of which are positive, some negative and some zero. Of all its constituent elementary particles, the sum is zero. If all the charged elementary particles of a neutral body were at rest (relative to the body itself) then the body would exert no net force on another similar neutral body because the forces exerted by the charged particles of the first body on the charged particles of the second body would exactly cancel. The force between two charged particles also depends on the relative velocity of these particles and therefore, considering that in neutral body, the negative particles (electrons) have high speeds (relative to the body itself) while the positive particles (protons) have small speeds, it is expected (as explained below) that the net electro-dynamic force between two neutral pieces of matter, that is, with electrical field and magnetic field is not zero.
Electric current is the flow of free electrons in the conductor. At any instant, the number of electrons leaving the wire is always equal to the number of electrons flowing from the battery into it. Hence, the net charge on the wire is zero.
Therefore, Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.