Hi there! The answer is D.
f(x) = | x | is the absolute value parent function. The most important characteristic of an absolute value function are the vertical stripes | |, surrounding an expression with at least x (or another variable) in it. The stripes make everything between the stripes positive. Mathematically the absolute value indicates the distance from a certain number to 0. Therefore | -7 | = 7 and | -x | = x
~ Hope this helps you!
