Does Splunk Cloud provide an option to select the location of the data being stored in the cloud? For example: in UK Based datacenters. This is about the cloud service, not the on-prem installation.
Yes you can choose which AWS region you want your splunk cloud instance to be deployed into. See list of available aws regions here: http://docs.splunk.com/Documentation/SplunkCloud/latest/Service/SplunkCloudservice