Many times I have to judge how much of a guess versus outright knowing it it was for me.
I usually look at the percentages that chose other answers and if it is around 10% or more then I go into a little more detail into those. I figure, there must be some kind of overlap I was not aware of that led people to that choice. The topics I tend to be really bad at, I read all of those explanations as well. Lately, since my test is next week it has been much less detail. I did 156 questions today...odd number because I wanted to round it out to 46 question blocks for the remainder.