Information security risk factors are the sources of uncertainty that may affect the confidentiality, integrity, or availability of information assets within an organization. Information security risk factors can include threats, vulnerabilities, or impacts that may compromise the security of information assets. Information security risk factors should be mitigated when developing in-house applications, which are software applications that are designed, developed, and maintained by the organization itself, rather than by external vendors or providers.
Mitigating information security risk factors when developing in-house applications canhelp prevent or reduce the occurrence or consequences of security incidents, such as data breaches, cyberattacks, unauthorized access, or data loss. The best way to ensure that information security risk factors are mitigated when developing in-house applications is to identify information security controls in the requirements analysis. The requirements analysis is the stage of the system development life cycle (SDLC) where the business needs and expectations of the application are defined and documented. The requirements analysis should include the functional and non-functional requirements of the application, such as the features, functions, performance, quality, reliability, and security of the application. Identifying information security controls in the requirements analysis can help ensure that the security requirements of the application are clearly specified and agreed upon by the stakeholders, and that they are aligned with the organization's security policies, standards, and regulations. Identifying information security controls in the requirements analysis can also help ensure that the security requirements are integrated into the design, development, testing, and deployment of the application, and that they are verified and validated throughout the SDLC. Identifying information security controls in the requirements analysis can also help ensure that the security requirements are traceable, measurable, and manageable, and that they can be monitored and reviewed for effectiveness and efficiency. References = THE SYSTEM DEVELOPMENT LIFE CYCLE (SDLC), p. 2-3, System Development Life Cycle - GeeksforGeeks, 7.3: Systems Development Life Cycle - Engineering LibreTexts, What Is SDLC? 7 Phases of System Development Life Cycle - Intetics.

A denial-of-service (DoS) attack is a type of cyberattack that aims to disrupt or disable the normal functioning of a system or network by overwhelming it with excessive traffic or requests.
The chief technology officer (CTO) has decided to accept the risk associated with the potential loss from a DoS attack. This means that the CTO has determined that the cost or effort of implementing or maintaining controls to prevent or reduce the impact of a DoS attack is not justified by the expected benefits or savings, and that the organization is willing to bear the consequences of a DoS attack if it occurs.
The best course of action for the risk practitioner in this situation is to identify key risk indicators (KRIs) for ongoing monitoring. This means that the risk practitioner should define and measure the metrics that provide information about the level of exposure to the DoS attack risk, such as the frequency, duration, or severity of the attacks, the availability, performance, or security of the systems or networks, the customer satisfaction, reputation, or revenue of the organization, etc.
Identifying KRIs for ongoing monitoring helps to track and evaluate the actual results and outcomes of the risk acceptance decision, compare them with the risk appetite and tolerance ofthe organization, identify any deviations or breaches that may require attention or action, and report them to the appropriate parties for decision making or improvement actions.
The references for this answer are:
Risk IT Framework, page 15
Information Technology & Security, page 9
Risk Scenarios Starter Pack, page 7

Detailed Explanation:Residual riskrefers to the risk that remains after mitigation measures have been applied.
It represents the exposure that an organization decides to accept, transfer, or further address, aligning with its risk appetite and tolerance.

Ineffective control implementation can result in increased risk exposure, reduced compliance, and diminished performance for the organization. Therefore, the most relevant information for stakeholders is the impact of ineffective control implementation on the business objectives, processes, and outcomes. The impact on business can include financial losses, reputational damage, operational inefficiencies, customer dissatisfaction, and legal liabilities. The other options are not as relevant as the impact on business, because they do not directly link the control effectiveness to the business value. References = Risk and Information Systems Control Study Manual, Chapter 4, Section 4.3.2, page 128.

The best way to resolve the concern where a control process has been implemented in response to a new regulatory requirement, but has significantly reduced productivity, is to escalate the issue to senior management. Senior management is the highest level of authority and responsibility in the organization, and they are responsible for setting the strategic direction, objectives, and risk appetite of the organization. Senior management should also oversee the risk management process, and ensure that the controls are aligned with the organization's goals and values. Escalating the issue to senior management can help to find a balance between complying with the regulatory requirement and maintaining the productivity of the organization. The other options are not as effective or desirable as escalating the issue to senior management, because they either ignore the problem, violate the regulation, or compromise the control.