What encompasses the processes used to test and ensure product quality?

The correct choice is Quality Assurance (QA) because it specifically refers to the systematic processes employed to ensure that a product meets certain quality standards and fulfills customer expectations. QA encompasses various activities, such as testing, monitoring, and reviewing the development processes to detect and prevent defects in the product. It emphasizes not just the end product, but also the means by which it is produced, ensuring that quality is built into the product from the ground up.

In the context of product development, QA plays a crucial role in establishing methodologies such as testing protocols, code reviews, and compliance checks that help maintain high-quality outputs throughout the product lifecycle. By implementing QA processes, a startup can establish reliability and trust with customers, which is essential for market success.

Integration refers to the process of combining various components of a system and does not specifically focus on product quality. Scalability is concerned with a product's ability to handle growth in users or transactions without compromising performance, while Technical Debt refers to the implied cost of additional rework caused by choosing an easy solution now instead of a better approach that would take longer, which can lead to future quality issues. Neither of these concepts directly addresses the processes involved in ensuring product quality, which is why they are not the correct choices.