attention grammarians!

[nolly]

"This index will show you the number and percent of students that selected specific answer options."

OR

"This index will show you the number and percent of students who selected specific answer options."

OR

something else?

Comments

[hopeforyou.livejournal.com]

Hmmm. I thought it would be "which", actually. Maybe I'm smoking crack, but I thought that "which" would refer back to "the number and percent" rather than "students" which is part of "of students".
The referring noun or direct object would be "the number and percent".

I used to learn this stuff by seeing if the sentence works without the prepositional phrase or indirect object. For example: "This index will show you the number and percent which selected specific answer options". I think "which have selected" is optimal, reading that.