What ISDN timer is started after Q.931 SETUP msg is sent?

What ISDN timer is started after Q.931 SETUP msg is sent?

A.
T301

B.
T303

C.
T302

D.
T310

E.
T305

Explanation:
http://www.net.com/support/manuals/html/isdnx/prsw601/prsw_33.html