In the context of a rapidly growing start-up like "ABC" providing a cloud-based IT management solution, implementing controls for Change Control & Configuration Management is essential to manage changes effectively in their production environment. Option A outlines a specific control related to managing the risks associated with changes to critical applications, customer-impacting systems, and infrastructure components. Given that ABC is dealing with cloud-based IT management and providing services to customers, ensuring that changes are controlled and assessed for potential impacts is crucial for maintaining the stability and security of their production environment.
Therefore, in this scenario, option A is the most suitable control to implement for Change Control & Configuration Management in ABC's rapidly growing cloud-based IT management start-up.