Exam 352-001 topic 1 question 9 discussion

Actual exam question from Cisco's 352-001

Question #: 9
Topic #: 1

A service provider has a Resilient Ethernet Protocol ring running as a metro backbone between its locations in one city. A customer wants to connect one site with one box redundant to the Resilient Ethernet Protocol ring at two different service provider locations. How can this be done without producing any Layer 2 loops within the network design?

A. Spanning tree at the service provider side only must be enabled.
B. Spanning tree at the customer side only must be enabled.
C. Flex Links at the service provider side only must be enabled.
D. Flex Links at the customer side only must be enabled.
E. EtherChannel at the service provider side and the customer side must be enabled.
F. Spanning tree at the service provider side and the customer side must be enabled.
G. Flex Links at the service provider side and the customer side must be enabled.