A "D-" passport is a is a very poor travel document. It does NOT provide access to the Schengen area or any of the developed countries. To receive a "D-" grade a passport must have a Travel Freedom score (Passport Score) between 10 and 23.
Additional Analysis:
The Travel Freedom score of this passport is 20%-50% lower than its simple count of visa-free countries. It means that this passport fails to provide access to the world's most attractive countries.