so I picked the right one, but I am sorta cheating having been a structural engineer for 10 yrs now

I get to work with much more advanced modeling codes but looks like SolidWorks is getting some nice capability, just depends on how accurate it is at predicting
Greg - the fact that the support went all the way to the edges is actually a good reason to select have selected it, so you actually do have an idea as to why you picked it. And theoretically the more fasteners the better so SW would predict 6 fasteners even better, tho' reality will show there is a limit to the value of additional fasteners.
Really there is no wrong answer since they all had positive safety factor
'course I could nit-pick the design and say it really doesn't have to go to the leading edge, I could save weight, optimize based on stress, etc and my bracket would look like none of the above, but I suspected what they were getting at which was screw the weight and efficiency and pick the best for load carrying capability.
So I guess the correct answer for overall best performance might be none of the above