Which type of athletic surface was first introduced in 1966 at the Houston Astrodome?

The correct answer is AstroTurf because it was the first synthetic turf introduced for athletic use during the opening of the Houston Astrodome in 1966. This innovative surface was designed to provide a consistent playing field that could withstand the rigors of sport, especially when natural grass struggled to thrive indoors under artificial lighting and other challenging conditions. AstroTurf revolutionized sports by offering a durable and low-maintenance alternative to traditional grass fields, impacting the design and management of athletic venues across various sports.

The other options, while they represent different types of surfaces, do not specifically relate to the development and introduction that marked the AstroTurf era in 1966. Grass turf remains a natural surface used widely, sand-based turf is a variant that emerged later, and natural clay is typically associated with tennis courts, none of which match the historical significance of AstroTurf introduced at that time.