You need to design an authentication strategy for users of portable computers. Your solution must meet business requirements. What should you do？（）

• A、Issue smart cards and smart card readers to all portable computer users. Configure the domain to require smart cards for login and to log off users who remote their smart cards
• B、Configure the portable computers to connect to only wireless networks that use Wired Equivalent Privacy （WEP）. Install digital certificates on all portable computers
• C、Install computer certificates on all portable computers. Configure all portable computers to respond to requests for IPSec encryption
• D、Install biometric authentication devices on all portable computers. Configure the Default Domain Policy GPO to require complex passwords for all users