The correct answer is 'Techniques and protocols for data encryption in transit and at rest'. When assessing a cloud service provider, confirming their data encryption methodologies is vital for ensuring data confidentiality and integrity. A cloud provider’s encryption practices, including the algorithms used, key management, and whether encryption is applied in transit and at rest, are crucial pieces of information for evaluating their security posture. 'Disaster recovery time objectives' are important but focus primarily on availability rather than confidentiality and integrity. 'Yearly employee turnover rates' may impact overall operational stability but does not have a direct correlation with data protection practices. 'Percentage of IT budget allocated to R&D' provides insight into the provider's investment in innovation, but it does not give a direct measure of how they handle and protect your data.