That is a HORRIBLY worded exam. Many of the questions in which the correct answer can be determined have as the correct answer something is itself not entirely correct. It's just the "least wrong" answer. Do you know which questions you are getting wrong?
For example, the question #13 on eye muscle surgery......it can prevent amblyopia but it can also be performed at any age. It's not likely to improve amblyopia beyond a certain age, but it can certainly be performed for cosmetic reasons. So it would seem that the "most correct" answer would be that it can prevent amblyopia but that's just the "least wrong" answer.
What course is this quiz for? Many of the questions on vision screening depend on which protocol you are using. There are a few different ones out there.
Yikes.