Refer to the exhibit.

Which statement about switch S1 is true?

A.
Physical port Fa0/13, Fa0/14, and Fa0/15 successfully formed a Layer 2 port-channel interface
using an open standard protocol.

B.
Logical port Fa0/13, Fa0/14, and Fa0/15 successfully formed a Layer 2 physical port-channel
interface using a Cisco proprietary protocol.

C.
Physical port Fa0/13, Fa0/14, and Fa0/15 successfully formed a Layer 3 port-channel interface
using a Cisco proprietary protocol.

D.
Logical port Fa0/13, Fa0/14, and Fa0/15 successfully formed a Layer 3 physical port-channel
interface using an open standard protocol.