To All Department Supervisors:

The Acme Records Retrieval System will be undergoing scheduled maintenance this Friday, from $4$:$00$ p$.$m$.$ to midnight. Please inform all department personnel of the system outage so that researchers can make alternative arrangements to access necessary data.

An archived copy of the Core Business Records Database will be accessible in the Web Services department office from $4$:$00$ p$.$m$.$ to $8$:$00$ p$.$m$.$ on Friday. However, this database contains only core records data and is limited in its scope.

Please direct any questions to Marcus Sampson, Web Services Maintenance Officer, at $(617)555-0004.$

The organizational structure of the above memo is best characterized as which of the following?

A$)$ Comparison$-$contrast

B$)$ Cause$-$effect

C$)$ Problem$-$solution

D$)$ Sequence