Gap analysis is a process of identifying and assessing the differences between the current state and desired state of an organisation or project. It helps to determine what needs to be done to achieve business objectives or solve business problems. Gap analysis typically involves three main steps: understand the existing situation, compare the desired situation and existing situation, and consider possible actions to address the gaps. Therefore, options A, B and C are correct answers, as they cover these steps in gap analysis. Option D is not a correct answer, as defining solutions to close gaps is not part of gap analysis itself, but rather a subsequent step that follows gap analysis. Gap analysis helps to identify what needs to be done, but not how it should be done. Option E is not a correct answer, as delivering solutions to close gaps is not part of gap analysis itself, but rather a final step that follows defining solutions. Gap analysis helps to identify what needs to be done, but not how it should be done or implemented.

References: BCS Practitioner Certificate in BAP Specimen, page 25.