Option B is the correct answer. Amazon SageMaker is a fully managed service that provides every developer and data scientist with the ability to build, train, and deploy machine learning models quickly. Amazon QuickSight is a scalable, serverless, embeddable, machine learning-powered business intelligence (BI) service built for the cloud. Using Amazon SageMaker for model development and training ensures minimal operational overhead due to its fully managed nature. Similarly, Amazon QuickSight allows for intuitive data visualization and integrates easily with SageMaker, making it the optimal solution for the e-commerce company's requirements.