You have proposed Aruba 8400 switches as core switches for a customer. The customer is very concerned about the network always being on and has indicated that no maintenance window is permitted even for a core switch software upgrade. What feature of this switch should you explain?

A. Backplane stacking
B. Network Analytics Engine (NAE)

C. Virtual Switching Extension (VSX)

D. ArubaOS-CX Python-based APIs

Reference: https://www.arubanetworks.com/assets/ds/DS_8400Series.pdf