Answer:
Option D
Explanation:
Given

Required
Determine if the function is quadratic

Start by representing the function as an x-y table
x:- 5 || 7 || 9 || 11
y:- 7 || 11 || 14 || 18
Next; Calculate the difference between the values of y



The resulting difference are: 4 || 3 || 4
Next; Calculate the difference between the difference of values of y


The resulting difference are: -1 || 1
For the function to be quadratic, the above difference must be the same and since they are not, then the function does not represent a quadratic function.
Option D answers the question