Article 690 is concerned with which of the following?

Article 690 of the National Electrical Code (NEC) specifically addresses Solar Photovoltaic Systems. This article outlines the requirements for the installation, operation, and maintenance of photovoltaic (PV) systems that generate electricity from sunlight. The focus includes topics such as safety requirements, system components, grounding, wiring methods, and connection to the electrical grid.

In the context of the options provided, the choices regarding natural and artificially made bodies of water, fire pumps, and emergency systems fall under different NEC articles, which deal with their specific electrical considerations and safety protocols. This highlights the specialized nature of Article 690, which is dedicated to the unique aspects of solar energy systems, ensuring they are safely integrated into the broader electrical infrastructure. Therefore, the focus on solar photovoltaic systems is what makes this answer the most accurate in relation to Article 690.