Refer to the exhibit.

The transceivers that the architect should recommend for each pair of switches are two QSPF+ MPO. This option would provide 40 Gbps bandwidth per link, which is enough to meet the customer requirement of 80 Gbps for the link aggregation. The QSPF+ MPO transceivers use a single multi-fiber connector that can support up to 12 fibers, which is compatible with the customer’s existing OM4 multi-mode fiber infrastructure. The QSPF+ MPO transceivers also support distances up to 100 meters, which is sufficient for the customer’s inter-building connections.

The other options are not optimal for the customer requirement because they either provide insufficient bandwidth or require additional fiber strands. Two QSPF+ BiDi transceivers would provide only 20 Gbps bandwidth per link, which is half of the customer requirement. Eight SFP+ LR or SR transceivers would provide 80 Gbps bandwidth per link, which is more than the customer requirement, but they would also require eight fiber strands per link, which is more than the customer’s available fiber infrastructure. References:

Aruba Transceiver and Cable Data Sheet (Aruba Networks)

Designing Aruba Solutions Study Guide (HPE Press)