The correct answer is "αδιανόητες" because it is the only option that matches the given context of the question. The question is asking for a word that describes something, and out of the three options provided, "αδιανόητες" is the only word that fits this description. The other options, "συχνό φαινόμενο" and "θρησκευτικές," do not align with the context given.