U can say that when i have taken date for visa interview at
that time my I-20 was came from that university only....

You can answer that collage is not good but faculties are good.

Dont show the I20 at all Its not there in their records 
unti u tell hem

The VOs know from what universities you've got the I20s. So
don't fake it if you have many I20s.

Give a good reason like "some unique subject", "Professor
John xxx is stationed at that university who does research
on xxx field which is my field of interest too" etc

The better answer is here. " it is one of the best
university among my admits, which suits to my profile."
thats enough... if visa officer expecting some thing then u
come to tell abt the university which provides me research
areas and good internships,which helps me in learnin the
subject depth thats it.

i choose thhis university because it does not discriminate 
about race or religion, it has some affirmative rigth which 
other universities have