To uphold code quality in Continuous Integration, Static Analysis tools are employed. These tools analyze the source code without executing it, identifying potential issues, code smells, or violations against predefined coding standards, thus ensuring high code quality before merging.

Integration Testing involves validating the interactions between different software modules or systems to ensure they work together as intended. It focuses on identifying issues that can arise when individual units or components are integrated, such as data inconsistencies, communication errors, or function mismatches.

Exploratory Testing is an unscripted approach to software testing where testers rely on their intuition, experience, and creativity to identify defects without predefined test cases. It emphasizes real-time learning, test design, and simultaneous test execution, allowing testers to continuously adapt their testing based on the results.

Stress testing involves deliberately overloading the system beyond its specified limits. The objective is to identify system weak points, ensure it fails gracefully, and understand how it behaves under extreme conditions.

Version Control systems allow multiple developers to work on the same project concurrently. When two developers make changes to the same piece of code, the version control system flags it as a merge conflict. The developers, possibly with the help of a lead or reviewer, will then resolve the conflict, ensuring that the final merged code retains the intended functionality from both changes.

The Test Lead is usually responsible for managing and leading the test team, which includes making key decisions related to test issues. While a Test Manager might have overarching responsibility and a Business Analyst might provide business perspective, it is the Test Lead who usually determines the severity and priority of a bug.

Automated testing is particularly suitable for regression tests, which need to be executed frequently to ensure that previously working functionality remains intact after any code changes or updates.

Beta Testing provides feedback from actual users in real-world settings. Usability issues flagged during Beta Testing are crucial as they provide insights into how the software is perceived by the end-users. The best approach would be to conduct a focused usability testing session to deeply understand the feedback, make necessary adjustments, and improve the software's usability.

In a Continuous Deployment setup, rapid feedback is essential to ensure the frequent releases don't break functionality. An Automation Tester plays a critical role here, as they set up automated test cases that can quickly validate the software's functionality after every release, ensuring rapid feedback without manual intervention.

Incremental integration testing involves integrating one component at a time, testing it, and then moving to the next, ensuring that defects are identified and corrected at each step. This approach is efficient in pinpointing issues.