Final answer:
Option (A), The development of the theory of modern light's origin was influenced by experiments that revealed light's wave-particle duality, including Young's double-slit experiments and Maxwell's electromagnetic theory, culminating in Einstein's concept of wave-particle duality.
Step-by-step explanation:
The discovery of the speed of light in a vacuum, observations of interference patterns in double-slit experiments, and the development of Maxwell's electromagnetic theory all significantly contributed to the contemporary understanding of the origin of modern light. The notion of wave-particle duality was iteratively built upon by experiments conducted by Thomas Young, which showed the wave characteristics of light, and further supported by James Clerk Maxwell, who indicated that light was an electromagnetic wave.
Albert Einstein's findings added to this framework by introducing the concept of wave-particle duality which unified the wave-like and particle-like nature of light. While light demonstrates wave-like behavior, as seen through interference patterns, it also exhibits particle-like properties, such as during the photoelectric effect.