A competency is a combination of skills, knowledge and behaviours that enable a person to perform a task or role effectively and efficiently. Therefore, option D is the correct answer, as it describes the competencies required for this role based on the job advert. Business case development is a competency that involves creating and presenting a formal written proposal that details the costs and benefits of a proposed business change or solution. It helps to justify and secure the approval and funding for a proposed business change or solution. This competency is required for this role, as the job advert states that the business analyst will assist in the development of formal written proposals detailing the cost and benefit of proposed business initiatives. Investigation techniques is a competency that involves using a variety of methods to explore and define complex situations or problems within an organisation or project. It helps to elicit, analyse, validate and prioritise the views and needs of stakeholders and identify the root causes and effects of situations or problems. This competency is required for this role, as the job advert states that the business analyst should be able to use a variety of methods to explore and define complex situations. Business architecture is a competency that involves designing and modelling the structure and relationships of an organisation or project at a high level of abstraction. It helps to understand how an organisation or project operates, delivers value and achieves its objectives and outcomes. This competency is required for this role, as the job advert states that the business analyst should have experience of producing blueprints in terms of processes, management structures, culture and people. Option A is not a correct answer, as it does not describe all the competencies required for this role based on the job advert. Subject matter expertise is a competency that involves having in-depth knowledge and understanding of a specific domain or industry within an organisation or project. It helps to provide insights and guidance on the best practices and standards within a specific domain or industry. This competency is not required for this role, as the job advert does not state that the business analyst should have subject matter expertise in any specific domain or industry. Option B is not a correct answer, as it does not describe all the competencies required for this role based on the job advert. Domain knowledge is a competency that involves having general knowledge and understanding of a broad domain or industry within an organisation or project. It helps to provide context and background on the nature and scope of a domain or industry. This competency is not required for this role, as the job advert does not state that the business analyst should have domain knowledge in any broad domain or industry. Gap analysis is a competency that involves comparing current and desired situations or problems and identifying the differences or gaps between them. It helps to determine what changes or improvements are needed to bridge the gaps and achieve desired situations or problems. This competency is not required for this role, as the job advert does not state that the business analyst should have experience of gap analysis. Option C is not a correct answer, as it does not describe all the competencies required for this role based on the job advert. Requirements engineering is a competency that involves eliciting, analysing, specifying, validating and managing requirements for a system or product within an organisation or project. It helps to ensure that requirements are clear, complete, consistent, testable and traceable throughout the system or product lifecycle. This competency is not required for this role, as the job advert does not state that the business analyst should have experience of requirements engineering.