Which option describes how this Cisco IOS SIP gateway, with an analog phone attached to its FXS port, handles an incoming informational SIP 180 response message without SDP?

Refer to the exhibit.

Which option describes how this Cisco IOS SIP gateway, with an analog phone attached to its FXS port, handles an incoming informational SIP 180 response message without SDP?
A. It will enable early media cut-through.
B. It will generate local ring back.
C. It will do nothing because the message is informational.
D. It will terminate the call because this is an unsupported message format.
E. It will take the FXS port offhook.