UMichigan's anatomy question bank is the best and most comptehensive question bank out there and this is linked at the top of the page! The question files also have explanations for the chosen answer. In addition, they have great questions and guides for radiology and gross anatomy. 

Other question banks 

• Teach me anatomy: in addition to good notes, teach me anatomy has multiple choice questions on each topic. They are limited for people who don't have a subscription, but it is worthwhile to purchase!
• Anatomy guy: there are questions using cadaveric prosections in this website.