MOV指令究竟访问那个段寄存器

MOV AX, [123456H] ；默认段寄存器DS 
MOV EAX, [EBX+EBP] ；默认段寄存器DS 
MOV EBX, [EAX+100H] ；默认段寄存器DS 
MOV EBX, [EBP+EBX] ；默认段寄存器SS 
MOV [ESP+EDX*2], AX ；默认段寄存器SS 
MOV AX, [ESP] ；默认段寄存器SS