Fictional Corp has a data center that runs multiple internal applications. However, they want to migrate their email to a cloud service provider so that mail will continue to be delivered in the case of any Internet service interruptions. They also want to use a single directory service so that they don't have to create duplicate user accounts on the internal and external systems. Which of the following types of services is best suited for Fictional Corp's needs? a. public cloud
b. private cloud
c. hybrid cloud
d. community cloud