IPA: /ʌnˈtʃælɪndʒɪŋ/
KK: /ʌnˈtʃælɪndʒɪŋ/
Something that is easy to do and does not require much effort or skill.
The test was unchallenging, and most students finished it quickly.
Unchallenging → It is formed from "un-" (meaning not) and "challenging" (from the verb "challenge", which comes from Old French *chalenge*, meaning to accuse or call to account). The word "unchallenging" means not presenting a challenge or difficulty.
Think of 'not' ('un-') making something 'challenging' easier — that's why unchallenging means something that is easy or does not pose a challenge.