Answer: Mean
Explanation:
The given data : 85, 78, 92, 98, 85.
We know that there are three main measures of central tendency : -
1) mode, 2) median 3) mean
1) Mode of the given data = Most repeated number = 85
2) For median first arrange the given data in order :-
78, 85, 85, 92, 98
Now, Median = Middlemost number = 85
3)

We can see that mean is giving the highest score (87.6) so she could show her teacher that she really understood her assignments.