The AcceptChanges method is commonly used after updating data in ADO.NET to commit changes to the underlying data source and clear the change tracking mechanism.

The correct option is 'Deletion or Removal'. The DeleteOnSubmit method in LINQ to SQL is used to mark an entity for deletion. It does not immediately delete the entity from the database but rather flags it for deletion. The actual deletion occurs when the SubmitChanges method is called on the DataContext. This method is commonly used to prepare objects for deletion before committing changes to the database.

When optimizing database table mappings in Entity Framework for better performance, it's essential to avoid over-fetching data by projecting only the required columns in queries. This reduces network overhead and improves query execution time. Additionally, using eager loading instead of lazy loading can help fetch related entities upfront, reducing the number of subsequent database calls. Implementing proper indexing on frequently queried columns enhances query performance by facilitating faster data retrieval. Minimizing round trips to the database by batching multiple operations into a single transaction reduces latency and improves overall throughput. These considerations help optimize the performance of Entity Framework applications by efficiently managing database interactions.

When dealing with Entity Framework performance, it's important to consider the "SQL Queries" of database queries generated by the mappings. Entity Framework translates LINQ queries into SQL queries to interact with the database. Understanding and optimizing the SQL queries generated by Entity Framework can significantly improve the performance of your application.

The correct option is OracleCommand. When working with Oracle databases in .NET applications, the OracleCommand class is specifically designed to execute commands against an Oracle database. It provides methods and properties to facilitate database interactions, making it the appropriate choice as a command object for Oracle databases.

Query optimization in LINQ involves techniques such as using appropriate indexes, selecting only necessary columns, and minimizing data transfer between the database and application to improve performance. It aims to eliminate unnecessary data retrieval and processing, thus enhancing query efficiency.

The ObjectDataSource control in ADO.NET streamlines the process of binding to custom business objects, hence the correct option is "ObjectDataSource".

The DataSet plays a crucial role in managing data synchronization in a multi-tier application architecture. It acts as an in-memory cache of data retrieved from the database and provides a disconnected data model, allowing data to be transferred between the presentation layer and the database in a flexible and efficient manner.

When deciding between Code-First and Database-First in Entity Framework, factors such as the existing database structure and the availability of visual modeling tools should be considered. Database-First is suitable when working with an existing database schema or when visual modeling is preferred. On the other hand, Code-First provides more control over the code and development process, making it suitable for projects where development speed and code control are essential.

In ADO.NET, parameters are passed to a stored procedure using SqlParameter objects. These objects allow for type-safe and secure parameter passing, helping prevent SQL injection attacks and ensuring correct data types.