When there are changes to regulations or any other factors that significantly impact the project, it's crucial to follow the change control process. This involves documenting the changes, assessing their impact on the project, and obtaining approval from relevant stakeholders before implementing the changes. Additionally, updating the risk register is essential to reflect the new risks introduced by the changes in regulations. Option A is the most appropriate choice because it emphasizes adherence to the change control process, which ensures that changes are managed in a controlled and documented manner. This approach helps in maintaining transparency and accountability in handling project changes, especially when dealing with regulatory requirements.