Answer:
d. Enrollment
Explanation:
Biometric refers to the machine in which it stores the data of the various persons i.e to by face recognition, fingerprint, etc
The enrollment is a procedure of a biometric in which a person is used for the one time. The information related to the person is created and stored
Therefore in the given case, for keeping the accurate recording of the person characteristic we need to enroll it
Hence, the option d is correct