The vertex of the parabola in the $x-y$ plane above is $(0,c)$. Which of the following is true about the parabola with the equation $y=a(x-b)^2+c ?$

Question

$\begin{array}{1 1} (a)\; \text{The vertex is (b,c) and the graph open upward.} \\ (b)\; \text{The vertex is (b,c) and the graph open downward. } \\ (c)\; \text{The vertex is (-b c) and the graph open upward.} \\ (d)\; \text{The vertex is (-b,c) and the graph open downward} \end {array}$