Mean because the mean is an average. That gives an overall understanding of what the entire class did.
I have memorized facts about fractions like these, so can tell you ...

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A fraction with 9 as a denominator is a repeating 1-digit decimal with the decimal digit being the numerator of the fraction.
A fraction with 11 as a denominator is a repeating 2-digit decimal with the two digits being 9 times the numerator of the fraction.
1/8 = 0.125, so any multiple of 1/8 is that multiple of 0.125.
You didn’t post the options but that is also equal to 1.0 x 10^-6
Answer:
Bottom left
< means that it's dashed line