A. Any diploma has as much credibility as the issuing organization. So it will depend on the person receiving the diploma information, whether employer, government agency (such as the military), or educational institution.
The GED is available as an alternative, if it's important. None of my three children had diplomas or GED's, but all three got into college. The older two graduated in four years from private colleges; both had partial scholarships. My third is still attending college.