单项选择题

执行MOV AX ,WDAT 指令,要使AX寄存器中内存为3412H,不能采用下列哪种数据定义?()

A.DSEG SEGMENT    WDAT EQU WORD PTR BDAT    BDAT DB  12H,34H    DSEG ENDS
B.DESG SEGMENT    BDAT DB 12H,34H    WDAT = WORD PTR BDAT    DSEG   ENDS
C.DESG SEGMENT    WDAT EQU THIS WORD    BDAT DB 12H,34H    DSEG ENDS
D.DESG SEGMENT    BDAT DB 12H,34H    WDAT LABEL WORD    DESG EBDS