A portion of the graph of f(x) = −x2 − 10x − 21 is shown. Which of the following describes all solutions for f(x)?

(x, x2 − 10x − 21), where −7 ≤ x ≤ −3
(x, y), where −7 ≤ x ≤ −3
(x, x2 − 10x − 21), where −8 ≤ x ≤ −2
(x, y) for all real numbers