You need to reduce read latency for the retail store solution. What are two possible ways to achieve the goal? Each correct answer presents a complete solution....

Azure Cosmos DB queries from the Azure Function exhibit high Request Unit (RU) usage and contain multiple, complex queries that exhibit high point read latency for large items as the function app is scaling.
B: A dedicated gateway is server-side compute that is a front-end to your Azure Cosmos DB account. When you connect to the dedicated gateway, it both routes requests and caches data.
You can provision a dedicated gateway to improve performance at scale.
You must connect to Azure Cosmos DB using the dedicated gateway in order to use the integrated cache. The dedicated gateway has a different endpoint from the standard one provided with your Azure Cosmos DB account. When you connect to your dedicated gateway endpoint, your application sends a request to the dedicated gateway, which then routes the request to different backend nodes. If possible, the integrated cache will serve the result.
C: Azure Cache for Redis perfectly complements Azure database services such as Cosmos DB. It provides a cost-effective solution to scale read and write throughput of your data tier. Store and share database query results, session states, static contents, and more using a common cache-aside pattern.
Reference:
https://docs.microsoft.com/en-us/azure/architecture/solution-ideas/articles/data-cache-with-redis-cache
https://docs.microsoft.com/en-us/azure/cosmos-db/dedicated-gateway