Hola Kathleen

When doing that quiz, the system gives you as correct answer the one using the indicative. As you are saying, this is an action that actually happens "every time she opens her presents...".

You chose the option using the subjunctive "abra" which is the incorrect one as we need the indicative here. The correct ending for the present subjunctive of abrir (for the él-ella form) is -a (abra), and the correct ending for the present indicative of abrir  (for the él-ella form) is -e (abre).

I hope this clarified it.

Saludos

Inma