Under the GDPR, which essential pieces of information must be provided to data subjects before collecting their personal

[answerhappygod]

Under the GDPR, which essential pieces of information must be provided to data subjects before collecting their personal data?

A. The authority by which the controller is collecting the data and the third parties to whom the data will be sent.
B. The name/s of relevant government agencies involved and the steps needed for revising the data.
C. The identity and contact details of the controller and the reasons the data is being collected.
D. The contact information of the controller and a description of the retention policy.