Homomorphic encryption employs which of the following techniques?

A$)$ Radom portions of a file are compared to a database in the cloud to verify authenticity

B$)$ Data is examined by the use of complex mathematical operations

C$)$ During transit, a file is injected with cypher text, which is extracted at the final destination

D$)$ Two files are entwined in a double helix pattern that resists hacking