how to remove unwanted region from binary image?

I'm working on a project.I am finding a technique to remove unwanted regions (small dots) from binary image. I have an image that includes object and some unwanted region. I want to remove it. Hence, I use some morphological operator example 'close' to remove. But it is not perfect. Along Original image and Expected Image in this post. Thanks in advance.

[Walter Roberson]

Duplicated by http://uk.mathworks.com/matlabcentral/answers/232267-how-to-remove-unwanted-region-from-binary-image