Let $g$ be a function with first derivative given by $g ^ { \prime } ( x ) = \int _ { 0 } ^ { x } e ^ { - t ^ { 2 } } d t$. Which of the following must be true on the interval $0 < x < 2$ ?
(A) $g$ is increasing, and the graph of $g$ is concave up.
(B) $g$ is increasing, and the graph of $g$ is concave down.
(C) $g$ is decreasing, and the graph of $g$ is concave up.
(D) $g$ is decreasing, and the graph of $g$ is concave down.
(E) $g$ is decreasing, and the graph of $g$ has a point of inflection on $0 < x < 2$.
Let $g$ be a function with first derivative given by $g ^ { \prime } ( x ) = \int _ { 0 } ^ { x } e ^ { - t ^ { 2 } } d t$. Which of the following must be true on the interval $0 < x < 2$ ?

(A) $g$ is increasing, and the graph of $g$ is concave up.

(B) $g$ is increasing, and the graph of $g$ is concave down.

(C) $g$ is decreasing, and the graph of $g$ is concave up.

(D) $g$ is decreasing, and the graph of $g$ is concave down.

(E) $g$ is decreasing, and the graph of $g$ has a point of inflection on $0 < x < 2$.