Final answer:
The Data Form Wizard in .NET applications uses OleDbDataAdapter, OleDbConnection, and OleDbCommand by default, which are part of ADO.NET for database operations. OleDbDataWriter and OleDbStatement are not actual ADO.NET classes, and OleDbDataReader is not created by the wizard by default.
Step-by-step explanation:
When using the Data Form Wizard in a .NET application, especially when working with databases, the classes involved are typically part of the ADO.NET architecture. These classes are designed to facilitate the connection, command, and data retrieval between a .NET application and a database.
The correct classes typically used by default are:
- OleDbDataAdapter - It serves as a bridge between a DataSet and a data source for retrieving and saving data.
- OleDbConnection - This class is used for establishing a connection to the data source.
- OleDbCommand - It is utilized to execute a command against the data source.
Therefore, the correct options that are used by default are:
- [B] OleDbDataAdapter
- [E] OleDbConnection
- [F] OleDbCommand
Classes such as OleDbDataWriter and OleDbStatement do not exist in ADO.NET, and the OleDbDataReader might be used to retrieve data in a forward-only manner, but it isn't created by default by the Data Form Wizard. It is often used in a more manual coding context when you need to read data sequentially.