From Longman Dictionary of Contemporary Englishtroublingtroub‧ling /ˈtrʌblɪŋ/ adjective worrying This incident raises troubling questions.
Examples from the Corpus
troubling• But while Manuela was a mirror in which I glimpsed troubling facets of my own personality, hers presented no problems.• But beyond them lies a more troubling general question.• He stopped worrying over the troubling knowledge which he could not quite remember.• The most troubling of these measures is the first, which is presumably for the benefit of the security services.• It provides a superficially plausible answer to deep and troubling questions about existence.• Besides, somehow she didn't want to be on her own with her troubling thoughts. 