You need to modify an ASP.NET page to prevent the browser window from going blank after a postback and to maintain the correct control focus after events are processed. What should you do?

A. Add the following attribute to the HTML code for the controls that cause the postbacks:
RunAt="client"

B. Add the following attribute to the HTML code for the controls that cause the postbacks:
EnableViewState="True"

C. Add the following attribute to the Page directive for the aspx file:
SmartNavigation="True"

D. Add the following attribute to the OutputCache directive for the aspx file:
Location="client