Which mechanism best describes how two cells with identical DNA can become a muscle cell and a neuron? Use conceptual reasoning about gene regulation.

Muscle cells and neurons have different mitochondrial DNA, which encodes the proteins responsible for the main functional differences between these cell types.

Gene duplication in early embryogenesis creates extra copies of muscle-specific genes in muscle progenitors while neuron progenitors keep copies of neural genes intact.

All cells express all genes equally; specialization is determined only by the nutrients around a cell at any moment and does not involve gene regulation.

Cell-type-specific transcription factors and epigenetic modifications selectively activate and repress different genes, leading to distinct protein expression patterns that produce specialized cell functions.