Ans: D
Consider the equation $y=a(x+b)^2$.
Consider the equation $y=a(x+b)^2$.
The sign of $a$ represents the direction of the opening of the parabola. If $a$ is positive, the graph opens upwards. If $a$ is negative, the graph opens downwards. According to the graph, the graph opens downwards. Therefore $a<0$.
$-b$ is the root of the graph. Since the root is now positive, then $-b>0$. Therefore $b<0$.
