Which function matches the slope field graph?
A) y = -(1/2)(t - 1)²
B) y = -(1/2)(t + 1)²
C) y = (1/2)t³
D) y = cos(t)

(B is the correct answer, but I'm unsure about how to get that. The lead-in question was finding two points where a solution curve has a critical point.)