Is it A, B, C, or D? I need help, please.

Answer:
D. 0
Step-by-step explanation:
|9 - 5| = |4|, which equals 4. |5 - 9| = |-4|, which also equals 4.
4 - 4 = 0.
If your answer is in absolute value and it is negative, the outcome will always be positive. Hope this helps.