I have been preparing for the PSM1 assessment for the last two weeks. Mostly relying on the scrum guide and the blog posts that point to recommended resources, tests. Recently landed on the PSM1 assessment here: https://www.thescrummaster.co.uk/professional-scrum-master-i-psm-i-practice-assessment
Scored 85% (17 correct out of 20 questions). Below questions went wrong: