What does ACI stand for?

ACI stands for the American Concrete Institute, which is a leading organization dedicated to advancing concrete knowledge, promoting concrete technology, and educating individuals in the field of concrete. The institute provides resources, standards, and certifications that ensure the quality, performance, and durability of concrete in various applications. It plays a critical role in establishing industry standards and practices that enhance safety and innovation in concrete construction.

The other options, while they might sound similar, do not reflect a recognized organization focused on concrete standards and education. The American Concrete Institute is well-established and respected globally, making it the correct choice in this context.