Discovery sampling is a type of statistical sampling that's used when the expected error rate in the population is very low1. This method is designed to discover at least one instance of an attribute or condition in a population1. It's often used in auditing to uncover fraud or noncompliance with rules and regulations1.
References:
What are sampling methods and how do you choose the best one?

Regular scanning of hard drives is the most effective way to detect installation of unauthorized software packages by employees because it can identify any software that is not approved by the organization and may pose a security risk or violate the software policy. Communicating the policy to employees is important, but it may not prevent or detect unauthorized software installation. Logging of activity on the network can monitor network traffic, but it may not capture all software installation events. Maintaining current antivirus software can protect the system from malicious software, but it may not detect all unauthorized software packages.
References:
* ISACA, CISA Review Manual, 27th Edition, 2020, p. 2381
* ISACA, CISA Review Questions, Answers & Explanations Database - 12 Month Subscription

The greatest resulting impact of project reporting not accurately reflecting current progress is that the project steering committee cannot provide effective governance. The project steering committee is a group of senior executives or stakeholders who oversee the project and provide strategic direction, guidance, and support.
The project steering committee relies on accurate and timely project reporting to monitor the project's status, performance, risks, issues, and changes. If the project reporting is inaccurate, the project steering committee cannot make informed decisions, resolve problems, allocate resources, or ensure alignment with the organizational goals and objectives.
The other options are not as impactful as option C. The project manager will have to be replaced is a possible consequence, but not the greatest impact, of inaccurate project reporting. The project manager is responsible for planning, executing, monitoring, controlling, and closing the project. The project manager may face disciplinary actions or termination if they fail to provide accurate and honest project reporting. However, this does not necessarily affect the overall governance of the project. The project reporting to the board of directors will be incomplete is a potential risk, but not the greatest impact, of inaccurate project reporting.
The board of directors is the highest governing body of an organization that sets the vision, mission, values, and policies. The board of directors may receive periodic or ad hoc project reporting to ensure that the project is aligned with the organizational strategy and delivers value. If the project reporting is inaccurate, the board of directors may lose confidence in the project or intervene in its management. However, this does not directly affect the day-to-day governance of the project. The project will not withstand a quality assurance (QA) review is a possible outcome, but not the greatest impact, of inaccurate project reporting. A quality assurance review is a process to evaluate the quality of the project's processes and deliverables against pred efined standards and criteria. A quality assurance review may reveal discrepancies or errors in the project reporting that may affect the credibility and reliability of the project. However, this does not necessarily affect the governance of the project. References: Project Steering Committee - Roles & Responsibilities, Project Reporting Best Practices, Quality Assurance in Project Management

Validation controls are used to check the input data from the user before processing it on the server. If the validation controls are moved from the server side to the browser, it means that the user can modify or bypass them using tools such as browser developer tools, JavaScript console, or proxy tools. This would increase the risk of a successful attack by structured query language (SQL) injection, which is a technique that exploits a security vulnerability in an application's software layer that allows an attacker to execute arbitrary SQL commands on the underlying database. SQL injection can result in data theft, data corruption, or unauthorized access to the system.
Buffer overflow, denial of service (DoS), and phishing are not directly related to the validation controls in a web application. Buffer overflow is a type of attack that exploits a memory management flaw in an application or system that allows an attacker to write data beyond the allocated buffer size and overwrite adjacent memory locations. DoS is a type of attack that prevents legitimate users from accessing a service or resource by overwhelming it with requests or traffic. Phishing is a type of attack that uses fraudulent emails or websites to trick users into revealing sensitive information or installing malware.
References:
Client-side form validation - Learn web development | MDN
JavaScript: client-side vs. server-side validation - Stack Overflow
SQL Injection - OWASP