Answer:
Option A. 6.25
Explanation:
The data shows the number of grams of fat found in different health bars is
11, 11.5, 10.5, 17, 14.5, 14.5, 18, 17, 19
Now we will arrange the data in ascending order
10.5, 11, 11.5, 14.5, 14.5, 17, 17, 18, 19
Middle of the numbers is 14.5 which is median of the data.
We know IQR = Median of first quartile - median of second quartile
Median of first quartile =

And median of second quartile =

Now IQR = 17.5 - 11.25 = 6.25
Therefore Option A 6.25 is the correct option.