You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4.0 to create a Windows Forms application.
You plan to deploy the application to several shared client computers. You write the following code segment.
(Line numbers are included for reference only.)

01 Configuration config = ConfigurationManager.OpenExeConfiguration(exeConfigName);
02 …
03 config.Save();
04 …

You need to encrypt the connection string stored in the .config file. Which code segment should you insert at line 02?

A.
ConnectionStringsSection section = config.GetSection(“connectionString”) as ConnectionStringsSection;
section.SectionInformation.ProtectSection(“DataProtectionConfigurationProvider”);

B.
ConnectionStringsSection section = config.GetSection(“connectionStrings”) as ConnectionStringsSection;
section.SectionInformation.ProtectSection(“DataProtectionConfigurationProvider”);

C.
ConnectionStringsSection section = config.GetSection(“connectionString”) as ConnectionStringsSection;
section.SectionInformation.ProtectSection(“RsaProtectedConfigurationProvider”);

D.
ConnectionStringsSection section = config.GetSection(“connectionStrings”) as ConnectionStringsSection;
section.SectionInformation.ProtectSection(“RsaProtectedConfigurationProvider”);

Explanation:
You encrypt and decrypt the contents of a Web.config file by using System.Configuration .DPAPIProtectedConfigurationProvider,
which uses the Windows Data Protection API (DPAPI) to encrypt and decrypt data, or System.Configuration.RSAProtectedConfigurationProvider, which
uses the RSA encryption algorithm to encrypt and decrypt data. When you use the same encrypted configuration file on many computers in a Web farm,
only System.Configuration.RSAProtectedConfigurationProvider enables you to export the
encryption keys that encrypt the data and import them on another server. This is the default setting.

CHAPTER 2 ADO.NET Connected Classes
Lesson 1: Connecting to the Data Store
Storing Encrypted Connection Strings in Web Applications (page 76)

Securing Connection Strings
(http://msdn.microsoft.com/en-us/library/89211k9b(v=vs.80).aspx)