As supervisor of the cancer registry, you report the registry's annual caseload to administration. the most efficient way to retrieve this information would be to use
a. patient abstracts. b. accession register. c. patient index. d. follow-up files.

.B. accession register

Explanation:

Registration is a term that originates in the Latin word regestum. It is about the action and the consequences of registering, a verb that refers to observing or inspecting something carefully. To register is also to write down or record a certain data in a document or paper.

In this case, being able to access the registry is the easiest and most efficient way to recover the information.