PDF checking the color space RGB CMYK

What does it show?

Returns the color space of elements found in pdf, and it indicates problem, if any.

How to interpret the result?

In terms of printing the pdf contains three important elements:
1. Images
2. Vector graphics elements
3. Text parts are shown with fonts and not as images in pdf.
Color space belongs to each of the three elements: RGB, CMYK, Gray, or some separate color.
What does the warning mean?
TGB cmyk color space
Rgb-cmyk conversion.
Rgb cmyk color space.
Pdf color space conversion.
Rgb color space is located in pdf, which will be converted to cmyk also by the printing office prior to printing.
How the problem could be resolved?
The rgb color space can be converted with the following converter: