Final answer:
The statement that black holes have the strongest force of gravity in the universe is generally true, as they are incredibly dense objects with gravitational fields so strong that they prevent even light from escaping.
Step-by-step explanation:
This statement is generally seen as true, given that black holes have gravitational fields so intense that nothing can escape, including light. These gravitational forces are so strong because of the immense density and mass concentrated in a very small region of space. Black holes result from gravitational collapse and are characterized by an event horizon that is proportional to their mass. Due to their density and mass, they have very high escape velocities, meaning that an object would have to travel faster than the speed of light to escape its gravity, which is not possible according to the laws of physics as we understand them. The concept of a black hole was theorized as early as the 18th century and was formalized with Einstein's theory of general relativity in 1916. Observational evidence, like that found by examining the supermassive black hole at the center of our Milky Way galaxy, which is estimated to have a mass of approximately 4 million solar masses, has accumulated over the years, confirming their existence.