In a cloud, a participating organization purchases and maintains the software and infrastructure itself.

"Private" is the right solution.

Explanation:

Application servers supplied sometimes over the World wide web or through a personal corporate network as well as to chosen customers rather than the community benefit of the entire, is termed as the private cloud.It provides companies with the advantages of a cloud environment that include self-checkout, adaptability as well as flexibility.

Ithink a is the answer.hope the answer is correct ☺

There’s also the option of making a new one