assume cs:codesg,ds:datasg,ss:stacksg
stacksg segment
dw 0,0,0,0,0,0,0,0
stacksg ends

datasg segment
db '1. display......'
db '2. brows........'
db '3. replace......'
db '4. modify.......'
datasg ends

codesg segment
start: mov ax,stacksg
       mov ss,ax
       mov sp,16
       mov ax,datasg
       mov ds,ax
       mov bx,0

       mov cx,4
   s0: push cx
       mov si,0
       mov cx,4
    s: mov al,[bx+3+si]
       and al,11011111b
       mov [bx+3+si],al
       inc si
       loop s

       add bx,16
       pop cx
       loop s0

       mov ax,4c00h
       int 21h
codesg ends
end start