You are creating a Windows application by using the .NET Framework 3.5.
The application contains a form to enter user details. The application must capture the preferred search
engine as part of input data.
You discover that the preferred search engine can be a known search engine or an unknown one.
You need to allow the user to select a value for the preferred search engine from a list of search engines.
You also need to allow the user to enter a value for the search engine in the same list.
Which control should you use?

A.
A ListBox control that has the SelectionMode property set to 1

B.
A TextBox control that has the AutoCompleteSource property set to Custom

C.
A ComboBox control that has the DropDownStyle property set to DropDown

D.
A ComboBox control that has the DropDownStyle property set to DropDownList