Quality assurance is defined as:

Quality assurance encompasses a number of defined practices aimed at ensuring that the final product meets the required standards and performance criteria. The correct choice states that quality assurance consists of actions taken to provide confidence in product performance. This definition highlights the essence of quality assurance as it relates to ensuring that materials and processes yield outcomes that fulfill or exceed expectations, both for safety and functionality.

By focusing on the confidence in product performance, this definition emphasizes the broader scope of quality assurance beyond mere compliance or regulatory actions, which are more narrowly defined. Quality assurance is proactive and systematic, involving processes from planning through execution to continuous monitoring, ensuring that the end result is reliable and effective.

In contrast, other definitions that might suggest quality assurance is limited to systematic actions by the contractor, only regulatory compliance, or confined to specific phases of construction are not as comprehensive. Quality assurance is an all-encompassing practice that integrates all steps within a construction project to produce a high-quality product.