问题：

[单选] Which statement best describes the differences between Cisco SMARTnet and Cisco SMARTnet Onsite？（）

A .  CiscoSMARTNet Onsite includes all of the elements of Cisco SMARTnet with the additionalprovision of onsite technician to perform parts replacement
B .  CiscoSMARTnet Onsite is primarily attractive to customers who do not need to replace theirhardware immediately， but would still like an onsite technician to install and replace hardware
C .  CiscoSMARTnet Onsite includes certification classes and live network consulting at thecustomer site
D .  CiscoSMARTnet Onsite provides network monitoring for small-to-medium sized businesses andprovides onsite technical resources when hardware problems are detecteD