Final answer:
Degeneracy pressure fails to stop gravitational contraction in a black hole, as its immense gravity crushes the core beyond the limit any known force can withstand.
Step-by-step explanation:
In which of the following objects does degeneracy pressure fail to stop gravitational contraction? The answer is a black hole. In white dwarfs and neutron stars, degeneracy pressure, arising from the Pauli exclusion principle, can halt gravitational collapse. However, in the case of a black hole, the mass of the star's core is so great (more than about three times that of the Sun) that gravity overwhelms all other forces, leading to an unstoppable collapse into an infinitely small volume.