Answer: The top graph.
Step-by-step explanation: The inflection is at x = 0, since the absolute value of x starts becoming greater as x decreases. E.g., at x = -2,
f(x) = |x| - 4
f(x) = |-2| - 4
f(x) = 2 - 4
f(x) = - 2
At x = -4
f(x) = |x| - 4
f(x) = |-4| - 4
f(x) = 4 - 4
f(x) = 0