Something to keep in mind is to get "inside the head" of the judges.
Here, the theme would appear to be "international education", so in my view, that would generally suggest something that shows off the 'international' aspect of things, preferably with something kind of educational.
As such, I eliminated those things that don't seem to be obviously 'foreign' which means 2, 3 & 4 had to go. Doesn't mean that these aren't nice landscapes, but rather that they lack a clear "sense of place" for the purpose of this contest's judges.
That leaves 1, 5, 6, and 7.
Of these, 6 gets dropped because it is underexposed and I'm not really sure if the composition can really do anything for me, even if recropped. I would have liked to have seen the ground in front of the statue, plus I probably would have wanted to move the point of view to the left (get the statue's hand away from the obelisk).
Between 1, 5 and 7, the first two don't have a cheery blue sky that makes it as appealing as 7. Plus 7 seems to have a "campus" sort of look to it, so that's why I ended up picking #7
-hh