对用户输入的数值限制为正数，如果输入了负数，则要求重新输入。下面__可以实现。A:Dim x As IntegerDo x = Val(InputBox(“请输入数据”))Loop While x < 0 B:Do x = Val(InputBox(“请输入数据”))Loop While x > 0 C:Do While x > 0 x = Val(InputBox(“请输入数据”))Loop D:x = Val(InputBox(“请输入数据”))If x < 0 ThenEnd If E:For x < 0 x = Val(InputBox(“请输入数据”))Next 答案: Dim x As IntegerDo x = Val(InputBox(“请输入数据”))Loop While x < 0