Theere are certain rules that apply:
1. f(x)+k = vertical shift
2. kf(x) = vertical stretch/shrink (depending)
3. f(x+k) = phase shift, also known as a horizantal shift.
4. f(kx) = Horizantal stretch/shrink
The answer to your question is C. I hope that this is the answer that you were looking for and it has helped you.
