The "Wheeler-DeWitt Equation" in quantum cosmology is used to:
a) Describe the quantum state of the entire universe, incorporating both general relativity and quantum mechanics, and aims to provide insights into the nature of the universe's initial conditions and its evolution.
b) Calculate the probability of particle collisions in high-energy physics.
c) Model the behavior of quantum fields in a curved spacetime.
d) Solve the classical equations of motion for particles in a gravitational field.