Briefing Android Knowledge

Which of the following two classes in the License Verification Library are main classes used to comm

Which of the following two classes in the License Verification Library are main classes used
to communicate with the licensing server?

A.
LicenseChecker and LicenseCheckerCallback.

B.
License and LicenseCallback.

C.
LicenseCallback and LicenseCheckerCallback.

D.
LicenseVerifier and LicenseVerifierCallback.