Which two components do southbound APIs use to communicate with downstream devices?

Which two components do southbound APIs use to communicate with downstream devices?
(Choose two.)
A. services running over the network
B. OpenFlow
C. external application APIs
D. applications running over the network
E. OpFlex

350-701: Implementing and Operating Cisco Security Core Technologies Free dumps for 350-701 in PDF format. High quality 350-701 PDF and software. VALID exam to help you pass.