The correct answer is C. x= 9; At level 9, 27 people will be contacted.
We are given that f(x) = 3*x, where x represents the level.
To find x when f(x) = 27, we need to solve the equation 3*x = 27 for x:
3*x = 27
Dividing both sides by 3, we get:
x = 9
Therefore, at level 9, 27 people will be contacted, and the correct answer is C.