A、to show thAt high sChool stuDEnts CAn BE vEry shy.
B．to ExplAin thAt Blushing is A lEArnED BEhAvior.
C．to provE thAt Blushing is not EAsily ControllE
D、
D、to sAy thAt his shynEss is morE sErious thAn hErs.