Your company has a Microsoft Exchange Server 2007 Service Pack 2 (SP2) environment with

Enterprise client access licenses (CALs) installed. Employees have Windows Mobile 6.5 devices. You manage the devices by using Microsoft Exchange ActiveSync. You deploy a certificate to the Windows Mobile devices, and configure an Exchange ActiveSync policy to allow only applications with this certificate to run on the Windows Mobile devices. You develop a custom Windows Mobile application. You deploy the application to the Windows Mobile devices. The application does not run. You need to ensure that the application can run on the Windows Mobile devices. What should you do?

A.
Sign the application executable using the existing certificate.

B.
Convert the root certificate authority (CA) certificate to a Base-64 Encoded x.509 certificate.

C.
On the Windows Mobile devices, install a Windows MarketPlace for Mobile certificate in the code-signing store.

D.
On the Windows Mobile devices, remove the existing certificate and then install it into the trusted root certificate store.