You are provisioning an E-1 circuit on an ONS 15454 SNCP configuration and XC-VXL-10G card.
 How many total ports are used within the Low-Order matrix at the source node？（）

A. It protects signals against node failures between rings.
B. It protects signals against node failure within a single ring.
C. It allows for traffic to be preempted when a ring switch occurs.
D. Traffic can be dropped and continued at interconnecting nodes.
E. It protects preemptible traffic from being dropped when a ring switch occurs.

A. only Slots 6 or 12
B. only Slots 3 or 15
C. high or low speed slots
D. directly adjacent to the working card
E. high-speed slots only （5/6 and 12/13）