A) true
In Coulomb's law, the force between two charges is given by the formula \( F = k \frac{|q_1 q_2|}{r^2} \), where \( F \) is the force, \( k \) is the electrostatic constant, \( q_1 \) and \( q_2 \) are the magnitudes of the charges, and \( r \) is the distance between the charges. The sign of the force is determined by the signs of the charges: if the product \( q_1 q_2 \) is negative, the force is attractive and therefore negative in terms of direction; this indicates that the charges are opposite (one is positive and the other is negative). Conversely, if the product is positive, the force is repulsive, indicating that both charges are of the same type (either both positive or both negative).