The correct answer is true.
It is true that Sir Isaac Newton not only described the law of gravity, but he also discovered a mathematical relationship to measure the force of gravity between any two objects.
It is well known that Isaac Newton was a man ahead of his time. He had a brilliant mathematician mind and could compare the acceleration of the moon with the acceleration of things on our planet. He discovered the dependence of gravity upon the distance of different objects.
It all started with the fall of an apple from the tree and ended up as the Isaac Newton Law of Universal Gravitation.