设（AL）= 21H，（BL）=32H，（CL）= 54H，执行下列程序段后AL的值为
CMP AL,BL
JG BBB
XCHG AL,BL
BBB: CMP AL, CL
JG CCC
XCHG AL, CL
CCC：INT 20H
A.54H
B.21H
C.32H
D.0A7H
