Which type of object should you use in the method?

You need to write a method that retrieves data from a Microsoft Access 2013 database.
The method must meet the following requirements:
Be read-only.
Be able to use the data before the entire data set is retrieved.
Minimize the amount of system overhead and the amount of memory usage.
Which type of object should you use in the method?

A.
SqlDataAdapter

B.
DataContext

C.
DbDataAdapter

D.
OleDbDataReader

Explanation:
OleDbDataReader Class
Provides a way of reading a forward-only stream of data rows from a data source.
Example:
OleDbConnection cn = new OleDbConnection();
OleDbCommand cmd = new OleDbCommand();
DataTable schemaTable;
OleDbDataReader myReader;
//Open a connection to the SQL Server Northwind database.
cn.ConnectionString = “Provider=SQLOLEDB;Data Source=server;User ID=login;
Password=password;Initial Catalog=Northwind”;