It is not. It's a multiple choice question regarding which religion molded German/European culture. If Judaism was included, Jews would bitch that having to choose between Christianity and Judaism was anti semitic. The answer, of course, is Christianity. It doesn't freakin' matter what other choices are presented. Some folks just love to be offended.
And if folks are so concerned about Germany not flagellating itself publicly and often enough about war crimes and atrocities, why do they want to e citizens? And if they don't what business is it of theirs.