which two types of SIP messages can the OGW use to tunnel a waiting QSIG message?

Refer to the exhibit.

During a QSIG tunneling over SIP call establishment, which two types of SIP messages can the
OGW use to tunnel a waiting QSIG message? (Choose two.)

A.
SIP re-INVITE

B.
SIP NOTIFY

C.
SIP INFO

D.
SIP OPTIONS

E.
SIP UPDATE

F.
SIP REFER