Answer:
Correct choice is B
Explanation:
All three functions are increasing when x is increasing. You can find values of each function when x is "enough large". For example, at x=100,
1. linear function:

2. exponential function:

3. quadratic function:

As you can see, when x approaches positive infinity, the exponential function will exceed both the linear and the quadratic functions.
Also you can use graphical method to get from the attached diagrams result. When x approaches positive infinity, the exponential function will exceed both the linear and the quadratic functions.
Correct choice is B.