Using the c-SRQM framework, a quantum description of the black hole singularity was introduced previously. According to the theory, a black hole singularity is made of a series of concentric spherical shells of a constant diametral step size A. Each shell was shown to be occupied with a fixed set of Primordial Stem Particles (PSP) of rest mass m_bar = h/Ac. The PSP appears to be defining a regime where the point-like and field-like particle physics meet. The innermost shell with diameter A, if it were to be found standing alone by itself, would be the smallest possible black hole in nature with mass of M_1 = Ac^2/4G, named the Unit Black Hole (UBH). In this article we have shown that the Beckenstein-Hawking entropy of black holes can be traced back to the available microstate arrangements of the PSPs on the singularity shells. The Page time and total evaporation time obtained from this theory are shown to be consistent with the existing theoretical predictions, a non-trivial hint to the consistency of the proposed theory.