Disabling tracking improves caching performance in Entity Framework. When tracking is disabled, Entity Framework does not keep track of changes to entities, resulting in reduced overhead and improved performance when caching query results.

Implementing a custom caching provider in Entity Framework involves developing a class that implements the IDbDependencyResolver interface. This interface allows customization of the caching mechanism used by Entity Framework, enabling integration with external caching solutions or the development of custom caching strategies tailored to application requirements. By implementing IDbDependencyResolver, developers can manage caching behavior and optimize performance based on specific use cases.

Entity Framework primarily utilizes "eager" caching to store query results. In eager loading, related entities are loaded along with the primary entity, improving performance by reducing database round-trips.

"Deferred" caching is utilized in Entity Framework to optimize performance by storing entity data across different requests. Deferred loading allows related entities to be loaded only when accessed, enhancing efficiency.

Data annotations such as "CachingEnabled" can be employed in Entity Framework to configure caching behavior on entities. By setting the "CachingEnabled" annotation, caching can be enabled or disabled for specific entities.

Raw SQL queries bypass caching mechanisms in Entity Framework. When using raw SQL queries, Entity Framework does not utilize its caching mechanisms, which can lead to reduced performance compared to using Entity Framework's query caching capabilities.

Implementing distributed caching in an application using Entity Framework involves creating a custom caching provider. This provider interfaces with the caching infrastructure to store and retrieve data from a distributed cache. This approach allows for flexibility in choosing the caching solution and provides control over caching strategies tailored to the specific application needs.

Cache synchronization in distributed Entity Framework applications can pose challenges, particularly regarding cache invalidation. Ensuring consistency across multiple cache instances and managing cache expiration to reflect changes in the underlying data can be complex. Inadequate synchronization strategies may lead to data inconsistency and stale cache entries, impacting application reliability and performance.

Option 2, OnQueryExecuted, is correct. This method allows developers to intercept queries after they've been executed, enabling custom caching solutions in Entity Framework.

Option 1, Cache-Aside, is correct. The Cache-Aside pattern involves checking the cache for an item before querying the database, allowing efficient cache invalidation in Entity Framework applications.