Final answer:
A negative charge, if free, will tend to move toward positive charges due to the electrostatic attraction between opposite charges. The correct answer is A.
Step-by-step explanation:
The question raised pertains to the basic principles of electric charges and their movement in an electric field. When a negative charge is free, it will naturally move toward positive charges due to the electrostatic force that attracts opposite charges, as per Coulomb's law.
This attraction occurs because positive and negative charges create an electric field around them. For a negative charge, the direction of the electric field is inward for other positive charges and outward for other negative charges. Consequently, this explains why a negative charge in the vicinity of a positive charge will experience a force pulling it towards the positive charge. The reverse is true for like charges; they repel each other. Therefore, negative charges move away from each other, and when placed in an electric field, they move toward regions of higher potential.
If a negative charge were placed at the center of a ring of uniform positive charge, it would be attracted uniformly from all sides by the ring and might not move if the ring's charge distribution remains perfectly symmetrical and uniform. However, if placed on the axis of the ring at a point other than the center, it would move towards the ring due to the resultant force towards the center of the ring.
In summary, the correct answer to the question is A. Toward positive charges. This is consistent with the fundamental principles of electrodynamics, including Coulomb's law and the concept of electric potential and fields.