A、BECAusE hE hAD A lEttEr oF thAnks.
B、BECAusE hE FEArED thAt hE might BE killED iF hE rEFusED、
C．BECAusE hE gAvE him A DEmAnD notE.
D．BECAusE hE showED him A ChEquE pAyABlE At sight.