14) What does the expression "coming up empty-handed" mean in the text (lines 13/14)? A  It means that studies on the education field are about t...

14) What does the expression "coming up empty-handed" mean in the text (lines 13/14)?

A  It means that studies on the education field are about to prove a correlation between homework and the students´ performance at school.
B  It means that studies on education found that there is a correlation between homework and the students´ performance at school.
C  It means that there is a hand full of evidences that homework contributes for the students´ academic achievements.
D  It means that studies on education have shown no evidence of the necessity of homework for students.
E  It means that educators have the power in their hands when it comes to deciding about assigning homework to their students.