To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) Cloud On-Demand - This option is incorrect because Cloud On-Demand is not the name of the Rackspace cloud service.
Option B) Cloud Servers - This option is correct because Cloud Servers is the name of the Rackspace cloud service.
Option C) EC2 - This option is incorrect because EC2 is the name of the cloud service provided by Amazon Web Services (AWS), not Rackspace.
Option D) None of the above - This option is incorrect because the correct answer is Option B, Cloud Servers.
The correct answer is B) Cloud Servers. This option is correct because Cloud Servers is the name of the Rackspace cloud service.