Final answer:
In Coulomb's law, the role analogous to mass in Newton's law of universal gravitation is charge, which means electric charges interact in a way that is mathematically similar to how masses interact gravitationally.
Step-by-step explanation:
In Newton's law of universal gravitation, the force between two masses is proportional to the product of the two masses which is a key concept of the law. The role of mass in Coulomb's law is analogous to the role of charge. Just as gravitational force is dependent on mass, electrostatic force in Coulomb's law is directly proportional to the product of the electric charges of the interacting bodies.
In Coulomb's law, the role of mass is played by charge. Coulomb's law describes the force between two electrically charged objects. It states that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
Therefore, the answer to the question is a) Charge.