How to give zero value to an object color in an image which is having less number of pixels than the rest of the objects in the image?

Hello everyone

I have an image which consist two colored fingers Say Red and Pink colores. Suppose the number of the pixels of the Pink colored Pixels are greater than the number of the pixels of the Red finger. In this case i want the Red finger's values Zero/black and return me an image which consist only the Pink colored Finger. Suggest me some MATALB dynamic code for this scenario. The Attached Picture Named as two-colors.PNG is an Example .. Thanks in Advance

[Image Analyst]

Also attach the binary image that you used to mask that RGB image. The operation will need to be done on that mask image.