PLEASE HELP I DONT UNDERSTAND

Answer:
B.
-4, 1, 5, 8
Step-by-step explanation:
Your domain is your set of x values.
Your points are as follows:
(-4, 8)
(8, 10)
(5, 4)
(1, 6)
(5, -9)
Your x-values here are -4, 8, 5, 1, and 5. Your domain only consists of unique x-values, so your domain consists of -4, 8, 5, and 1.