quEstions 15-18 ArE BAsED on thE Following DiAloguE: whAt wErE thE mAssAChusEtts Colonists thAnkFul ForA．thE tErriBlE wintEr.
B．thE Corn hArvEst.
C．thE DEvElopmEnt oF thAnksgivingDAy.
D、For gEtting thE wholE FAmily togEthEr.