Self-seeking as an adjective is mindful of, or promoting only ones own interests while Opportunism as a noun is the taking of opportunities; especially the practice of seeking immediate advantage from a situation without considering the long term
Part of speech: adjective
Definition: Mindful of, or promoting only ones own interests
Part of speech: noun
Definition: The taking of opportunities; especially the practice of seeking immediate advantage from a situation without considering the long term
We hope you now know whether to use Self-seeking or Opportunism in your sentence.